Anti-CD38 antibodies and fusions to attenuated interferon alpha-2B

ABSTRACT

Antibodies that specifically bind to CD38, as well as constructs comprising such antibodies fused to attenuated interferon alpha-2B proteins are provided. Anti-CD38-attenuated interferon alpha-2b fusion constructs may be used to inhibit proliferation in cancerous cells that express both CD38 and the receptor for IFN-alpha2b, as well as to induce apoptosis in such cells. Inhibition of proliferation and induction of apoptosis in cancerous cells may serve as the basis for the treatment of the underlying cancer.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a divisional of U.S. application Ser. No. 14/922,282, filed Oct. 26, 2015, which is a continuation of International Application No. PCT/US2013/038659, filed on Apr. 29, 2013, the disclosure of each of which are hereby incorporated by reference their entirety.

REFERENCE TO A SEQUENCE LISTING

This application includes a Sequence Listing submitted electronically as a text file named 102085 000916 SL.txt, created on Jul. 11, 2018 with a size of 519,931 bytes. The Sequence Listing is incorporated by reference herein.

FIELD OF THE DISCLOSURE

This disclosure relates generally to the field of antibody engineering. More specifically, this disclosure relates to antibodies that bind specifically to CD38, as well as constructs comprising such antibodies and attenuated interferon-alpha ligands, and methods of treatment using these constructs. In these constructs, the antibodies direct the ligands to cells that express both CD38 and receptors for the ligands, and the attenuated interferon-alpha reduces interferon signaling in cells that do not express CD38.

BACKGROUND OF THE DISCLOSURE

Various publications, including patents, published applications, technical articles, scholarly articles, and gene or protein accession numbers are cited throughout the specification. Each of these materials is incorporated by reference herein, in its entirety and for all purposes.

CD38 is a 46 kDa type II transmembrane glycoprotein. It has a short N-terminal cytoplasmic tail of 20 amino acids, a single transmembrane helix and a long extracellular domain of 256 amino acids. It is expressed on the surface of many immune cells including CD4 and CD8 positive T cells, B cells, NK cells, monocytes, plasma cells and on a significant proportion of normal bone marrow precursor cells. In some instances, the expression of CD38 in lymphocytes may be dependent on the differentiation and activation state of the cell, for example, resting T and B cells may be negative while immature and activated lymphocytes may be predominantly positive for CD38 expression. CD38 mRNA expression has been detected in non-hemopoeitic organs such as the pancreas, brain, spleen and liver (Koguma, T. (1994) Biochim. Biophys. Acta 1223:160).

CD38 is a multifunctional ectoenzyme that is involved in transmembrane signaling and cell adhesion. It is also known as cyclic ADP ribose hydrolase because it can transform NAD⁺ and NADP⁺ into cADPR, ADPR and NAADP, depending on extracellular pH. These products induce Ca²⁺-mobilization inside the cell, which can lead to tyrosine phosphorylation and activation of the cell. CD38 is also a receptor that can interact with a ligand, CD31. Activation of receptor via CD31 leads to intracellular events including Ca²⁺ mobilization, cell activation, proliferation, differentiation and migration.

CD38 is expressed at high levels on multiple myeloma cells, in most cases of T- and B-lineage acute lymphoblastic leukemias, some acute myelocyticleukemias, follicular center cell lymphomas and T lymphoblastic lymphomas. CD38 is also expressed on B-lineage chronic lymphoblastic leukemia (B-CLL) cells. In some cases, B-CLL patients presenting with a CD38+ clone are characterized by an unfavorable clinical course with a more advanced stage of disease, poor responsiveness to chemotherapy and shorter survival time. The use of antibodies to CD38 has been proposed for the treatment of CD38-expressing cancers and hematological malignancies. It may therefore be advantageous to provide alternative antibodies to CD38 which have desirable manufacturing, stability and immunogenic properties.

Numerous peptide and polypeptide ligands have been described to function by interacting with a receptor on a cell surface, and thereby stimulating, inhibiting, or otherwise modulating a biological response, usually involving signal transduction pathways inside the cell that bears the said receptor. Examples of such ligands include peptide and polypeptide hormones, cytokines, chemokines, growth factors, and apoptosis-inducing factors.

Due to the biological activities of such ligands, many have potential uses as therapeutics. Several peptide or polypeptide ligands have been approved by regulatory agencies as therapeutic products including, for example, human growth hormone, insulin, interferon (IFN)-alpha2b, IFN-alpha2a, IFNβ, erythropoietin, G-CSF and GM-CSF.

While these and other ligands have demonstrated potential in therapeutic applications, they may also exhibit toxicity when administered to human patients. One reason for toxicity is that most of these ligands trigger receptors on a variety of cells, including cells other than those that mediate the desired therapeutic effect. A consequence of such “off target” activity of ligands is that many ligands are currently not suitable for use as therapeutic agents because the ligands cannot be administered at sufficiently high dosages to produce maximal or optimal therapeutic effects on the target cells which mediate the therapeutic effect.

For example it has been known since the mid-1980's that interferons, in particular IFN-alpha, are able to increase apoptosis and decrease proliferation of certain cancer cells. IFN-alpha has been approved by the FDA for the treatment of several cancers including melanoma, renal cell carcinoma, B cell lymphoma, multiple myeloma, chronic myelogenous leukemia (CML) and hairy cell leukemia. A direct effect of IFN-alpha on the tumor cells is mediated by the IFN-alpha binding directly to the type I IFN receptor on those cells and stimulating apoptosis, terminal differentiation or reduced proliferation. A further indirect effect of IFN-alpha on non-cancer cells is to stimulate the immune system, which may produce an additional anti-cancer effect by causing the immune system to reject the tumor.

These biological activities are mediated by type I interferon receptors on the surface of the cancer cells which, when stimulated, initiate various signal transduction pathways leading to reduced proliferation and/or the induction of terminal differentiation or apoptosis. The type I interferon receptor is, however, also present on most non-cancerous cells. Activation of this receptor on non-cancerous cells by IFN-alpha causes the expression of numerous pro-inflammatory cytokines and chemokines, leading to toxicity and untoward effects. Such toxicity may cause severe flu-like symptoms, which prevents the dosing of IFN-alpha to a subject at levels that exert the maximum anti-proliferative and pro-apoptotic activity on the cancer cells.

When IFN-alpha2b is used to treat multiple myeloma, its utility resides, at least in part, in its binding to type I interferon receptors on the myeloma cells, which in turn triggers apoptosis and/or reduced proliferation and hence limits disease progression. Unfortunately, however, this IFN also binds healthy cells within the body, triggering a variety of other cellular responses, some of which are harmful.

A publication by Ozzello (Breast Cancer Research and Treatment 25:265-76, 1993) describes chemically conjugating human IFN-alpha to a tumor-targeting antibody, thereby localizing the direct inhibitory activity of IFN-alpha to the tumor as a way of reducing tumor growth rates, and demonstrated that such conjugates have anti-tumor activity in a xenograft model of a human cancer. The mechanism of the observed anti-cancer activity was attributed to a direct effect of IFN-alpha on the cancer cells, since the human IFN-alpha used in the experiments did not interact appreciably with the murine type I IFN receptor, which could have led to an indirect anti-cancer effect. Because of this lack of binding of the human IFN-alpha to the murine cells, the toxicity of the antibody-IFN-alpha conjugate relative to free INF-alpha was not assessed.

Antibodies and IFN-alpha may also be connected together in the form of a fusion protein. For example, WO 01/97844 describes a direct fusion of human IFN-alpha to the C-terminus of the heavy chain of an IgG specific for the tumor antigen CD20.

In general, IFN may be targeted to cancer cells. While this approach may result in an increase in activity of the IFN against cancer cells, it does not completely address the issue of undesired activity of the IFN on healthy cells. Fusing IFN-alpha to the C-terminus of the heavy chain of an IgG may prolong the half-life of the IFN alpha leading to undesirable adverse events. Accordingly, there exists a need to decrease off-target activity of ligand-based drugs, while retaining the “on-target” therapeutic effect of such ligands.

SUMMARY OF THE DISCLOSURE

The disclosure features new anti-CD38 antibodies and constructs comprising an anti-CD38 antibody and attenuated IFN-alpha. The antibodies, which comprise one or a plurality of mutations in their heavy and/or light chain variable regions retain the ability to specifically bind to CD38, including CD38 expressed on the surface of cells. The antibodies may be fused, for example, to an attenuated form of interferon alpha to form an anti-CD38 antibody-attenuated interferon fusion construct.

In some aspects, an isolated antibody that binds specifically to CD38 comprises a heavy chain variable region comprising the amino acid sequence of SEQ ID NO: 559 and a light chain variable region comprising the amino acid sequence of SEQ ID NO: 664. In some aspects, an isolated antibody that binds specifically to CD38 comprising a heavy chain variable region comprising the amino acid sequence of SEQ ID NO: 665 and a light chain variable region comprising the amino acid sequence of SEQ ID NO: 666. In some aspects, an isolated antibody that binds specifically to CD38 comprises a heavy chain variable region comprising the amino acid sequence of SEQ ID NO: 739 and a light chain variable region comprising the amino acid sequence of SEQ ID NO: 664. The heavy chain variable region amino acid sequence of SEQ ID NO: 559 excludes the amino acid sequence of SEQ ID NO: 13. The light chain variable region amino acid sequence of SEQ ID NO: 664 excludes the amino acid sequence of SEQ ID NO: 14. In some aspects, an isolated antibody that binds specifically to CD38 comprises a heavy chain CDR1 comprising the amino acid sequence of, SEQ ID NO: 200, SEQ ID NO: 514 or SEQ ID NO: 697, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 202, SEQ ID NO: 516, SEQ ID NO: 544, SEQ ID NO: 698 or SEQ ID NO: 737, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 204, SEQ ID NO: 222, SEQ ID NO: 518, SEQ ID NO: 534, SEQ ID NO: 535, SEQ ID NO: 536, SEQ ID NO: 699 or SEQ ID NO: 738, and may further comprise a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 233, SEQ ID NO: 319, SEQ ID NO: 583, SEQ ID NO: 590 or SEQ ID NO: 696, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 235, SEQ ID NO: 307, SEQ ID NO: 311, SEQ ID NO: 585, SEQ ID NO: 591 or SEQ ID NO: 605, a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 237, SEQ ID NO: 321, SEQ ID NO: 324, SEQ ID NO: 587 or SEQ ID NO: 594.

In preferred aspects, the heavy chain variable region comprises the amino acid sequence of SEQ ID NO: 34, SEQ ID NO: 18, SEQ ID NO: 665, SEQ ID NO: 165, SEQ ID NO: 166, SEQ ID NO: 167, SEQ ID NO: 179, SEQ ID NO: 180, SEQ ID NO: 156, SEQ ID NO: 197, SEQ ID NO: 152, SEQ ID NO: 720, SEQ ID NO: 721, SEQ ID NO: 722, SEQ ID NO: 723, SEQ ID NO: 739, SEQ ID NO: 740, SEQ ID NO: 741, SEQ ID NO: 742, SEQ ID NO: 728, SEQ ID NO: 730, SEQ ID NO: 731. In preferred aspects, the light chain variable region comprises the amino acid sequence of SEQ ID NO: 65, SEQ ID NO: 68, SEQ ID NO: 86, SEQ ID NO: 88, SEQ ID NO: 92, SEQ ID NO: 93, SEQ ID NO: 660, SEQ ID NO: 661, SEQ ID NO: 662, SEQ ID NO: 663. SEQ ID NO: 161, SEQ ID NO: 184, SEQ ID NO: 185, SEQ ID NO: 188, SEQ ID NO: 198 or SEQ ID NO: 700, SEQ ID NO: 701, SEQ ID NO: 704, SEQ ID NO: 705, SEQ ID NO: 706, SEQ ID NO: 707, SEQ ID NO: 708, SEQ ID NO: 709, SEQ ID NO: 710, SEQ ID NO: 711.

The antibody preferably is capable of binding to CD38-positive cells. The antibody may bind to a CD38-positive cell with an EC50 value of less than about 100 nM. The antibody may bind to a CD38-positive cell with an EC₅₀ value of less than about 75 nM. The antibody may bind to a CD38-positive cell with an EC₅₀ value of less than about 50 nM. The antibody may bind to a CD38-positive cell with an EC₅₀ value of less than about 30 nM. The antibody may bind to a CD38-positive cell with an EC₅₀ value of less than about 25 nM. The antibody may bind to a CD38-positive cell with an EC₅₀ value of less than about 20 nM. The antibody may bind to a CD38-positive cell with an EC₅₀ value of less than about 15 nM. The antibody may bind to a CD38-positive cell with an EC₅₀ value of less than about 13 nM. The antibody may bind to a CD38-positive cell with an EC₅₀ value of less than about 10 nM.

The antibody may be a monoclonal antibody, and is preferably a fully human antibody. The antibody may comprise an FAb. The antibody may comprise a human IgG1 constant region or a human IgG4 constant region. The IgG1 or the IgG4 constant region may comprise a tyrosine at position 252, a threonine at position 254, and a glutamic acid at position 256 according to the EU numbering system. The IgG4 constant region may comprise a proline at position 228 according to the EU numbering system, and the proline at position 228 may be in addition to a tyrosine at position 252, a threonine at position 254, and a glutamic acid at position 256.

In some aspects, the antibody is fused to attenuated interferon alpha-2b. The interferon alpha-2b may comprise a substitution of the alanine at position 145 to glycine or aspartic acid, including an interferon alpha-2b having the amino acid sequence of SEQ ID NO: 649 or SEQ ID NO: 651. The attenuated interferon alpha-2b may be fused directly to the C-terminus of the IgG1 or IgG4 constant region, and the antibody may comprise the amino acid sequence of SEQ ID NO: 9, SEQ ID NO: 10, SEQ ID NO: 652, SEQ ID NO: 653, SEQ ID NO: 654, SEQ ID NO: 655, SEQ ID NO: 656, SEQ ID NO: 657, SEQ ID NO: 658, or SEQ ID NO: 694. The antibody, including the antibody fused to an attenuated interferon alpha-2b may be comprised in a composition comprising a pharmaceutically acceptable carrier.

Isolated polynucleotides encoding the antibody and the antibody fused to an attenuated interferon alpha-2b are provided. The polynucleotide may comprise the nucleic acid sequence of SEQ ID NO: 667, SEQ ID NO: 670, SEQ ID NO: 671, SEQ ID NO: 672, SEQ ID NO: 673, SEQ ID NO: 674, SEQ ID NO: 668, SEQ ID NO: 669, SEQ ID NO: 675, SEQ ID NO: 676, or SEQ ID NO: 677, SEQ ID NO: 678, SEQ ID NO: 679, SEQ ID NO: 680, SEQ ID NO: 681, SEQ ID NO: 682, SEQ ID NO: 683, SEQ ID NO: 684, SEQ ID NO: 685, SEQ ID NO: 686, SEQ ID NO: 687, SEQ ID NO: 688, SEQ ID NO: 689, SEQ ID NO: 690, SEQ ID NO: 691, SEQ ID NO: 692, SEQ ID NO: 693, SEQ ID NO: 695 SEQ ID NO: 702, SEQ ID NO: 703, SEQ ID NO: 712, SEQ ID NO: 713, SEQ ID NO: 714, SEQ ID NO: 715, SEQ ID NO: 716, SEQ ID NO: 717, SEQ ID NO: 718, SEQ ID NO: 719, SEQ ID NO: 724, SEQ ID NO: 725, SEQ ID NO: 726, SEQ ID NO: 727 SEQ ID NO: 732, SEQ ID NO: 733, SEQ ID NO: 734, SEQ ID NO: 735, SEQ ID NO: 743, SEQ ID NO: 744, SEQ ID NO: 745, SEQ ID NO: 746. The polynucleotides may comprise a vector. The vector may be used, for example, to transform a cell. A transformed cell comprising such polynucleotides is also provided. The transformed cell may comprise a mammalian cell, a yeast cell, or an insect cell.

Stable cells that express the antibodies are also provided. Antibody-expressing cells may be mammalian cells. Preferred cells are Chinese Hamster Ovary (CHO) cells.

Kits comprising antibodies fused to attenuated interferon alpha-2b are provided. The kits comprise the anti-CD38-attenuated interferon alpha-2b fusion construct, and instructions for using the construct in a method for inhibiting the proliferation of a tumor cell expressing CD38 and a receptor for interferon alpha-2b on its surface, instructions for using the construct in a method for inducing apoptosis in a tumor cell expressing CD38 and a receptor for interferon alpha-2b on its surface, instructions for using the construct in a method for treating a tumor comprising cells expressing CD38 and a receptor for interferon alpha-2b on their surface in a subject in need thereof, and optionally, a pharmaceutically acceptable carrier. Kits comprising anti-CD38 antibodies are provided, and such kits comprise the anti-CD38 antibody and instructions for using the antibody in a method for detecting a CD38-positive tumor cell in a tissue sample isolated from a subject, the antibody may optionally be fused to an attenuated interferon alpha-2b protein.

The anti-CD38 antibody-attenuated interferon alpha-2b fusion constructs may be used as a therapy in the treatment of a tumor comprising cells expressing CD38 and a receptor for interferon alpha-2b on their surface. Generally, a treatment method comprises administering to a subject having the tumor an anti-CD38 antibody-attenuated interferon alpha-2b fusion construct in an amount effective to treat the tumor. The construct may comprise any construct described or exemplified herein. The subject is preferably a mammal, more preferably a non-human primate, and most preferably a human being. The tumor may comprise a B-cell lymphoma, multiple myeloma, non-Hodgkin's lymphoma, chronic myelogenous leukemia, chronic lymphocytic leukemia or acute myelogenous leukemia.

The anti-CD38 antibodies, optionally fused to an attenuated interferon alpha-2b protein, may be used in a method for detecting a CD38-positive tumor cell in a tissue sample isolated from a subject. Generally, the method comprises contacting an antibody that binds specifically to CD38 with a tissue sample isolated from a subject and detecting a complex of the antibody and a CD38-positive cell in the tissue sample. The tissue sample may be known to have or be suspected of having CD38-positive tumor cells. The tissue may comprise blood or bone marrow. The CD38-positive tumor cell may be a CD38-positive B-cell lymphoma cell, multiple myeloma cell, non-Hodgkin's lymphoma cell, chronic myelogenous leukemia cell, chronic lymphocytic leukemia cell, or acute myelogenous leukemia cell. The subject is preferably a mammal, more preferably a non-human primate, and most preferably a human being. The method may include the step of isolating the tissue sample from the subject. The method may further comprise contacting the antibody with a tissue sample that does not include any CD38-positive cells, for example, to serve as a negative control.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows an example of an anti-CD38-attenuated interferon fusion construct.

FIGS. 2A and 2B show sequences of heavy chain variable regions of X02.1, related constructs and the most homologous germline antibody sequence. CDRs defined by the Kabat numbering system are underlined.

FIGS. 3A and 3B show sequences of light chain variable regions of X02.1, related constructs and the most homologous germline antibody sequence. CDRs defined by the Kabat numbering system are underlined.

FIGS. 4A-4D show the sequences of light chain variable regions of A02.1 and related constructs. CDRs defined by the Kabat numbering system are underlined

FIG. 5 shows the consensus variable heavy chain sequence of A02.1 and related constructs. Boxed regions contain CDRs (as indicated) as defined by the Kabat numbering system and the enhanced Chothia numbering system. CDRs defined by the Kabat numbering system are shown in bold. CDRs defined by the enhanced Chothia numbering system are underlined.

FIG. 6 shows the consensus variable light chain sequence of A02.1 and related constructs. Boxed regions contain CDRs (as indicated) as defined by the Kabat numbering system and the enhanced Chothia numbering system. CDRs defined by the Kabat numbering system are shown in bold. CDRs defined by the enhanced Chothia numbering system are underlined

FIGS. 7A-7C show sequences of heavy chain variable regions of humanized heavy chain variable regions. CDRs defined by the Kabat numbering system are underlined.

FIGS. 8A-8C show sequences of heavy chain variable regions of humanized light chain variable regions. CDRs defined by the Kabat numbering system are underlined.

FIGS. 9A and 9B show the variable heavy chain of A10.0 and related constructs. CDRs defined by the Kabat numbering system are underlined.

FIGS. 10A and 10B show the variable light chain of A10.0 and related constructs. CDRs defined by the Kabat numbering system are underlined.

FIGS. 11A and 11B show the variable heavy chain consensus sequence of A10.0 and related constructs. Boxed regions contain CDRs (as indicated) as defined by the Kabat numbering system and the enhanced Chothia numbering system. CDRs defined by the Kabat numbering system are shown in bold. CDRs defined by the enhanced Chothia numbering system are underlined.

FIG. 12 shows the variable light chain consensus sequence of A10.0 and related constructs. Boxed regions contain CDRs (as indicated) as defined by the Kabat numbering system and the enhanced Chothia numbering system. CDRs defined by the Kabat numbering system are shown in bold. CDRs defined by the enhanced Chothia numbering system are underlined.

FIG. 13 shows the binding activity of A02.1 variants to the CD38-expressing multiple myeloma cell line ARP-1 as measured by flow cytometry. The assay details are described in the Examples of this specification.

FIG. 14 shows the binding activity of A02.1 variants to the CD38-expressing multiple myeloma cell line NCI-H929 as measured by flow cytometry. The assay details are described in the Examples of this specification.

FIGS. 15 and 16 show the anti-proliferative activity of A02.1 variants on the multiple myeloma cell line ARP-1. A-isotype is an irrelevant specificity antibody fused with the attenuated interferon as a control. The assay details are described in the Examples (Cell proliferation assay).

FIG. 17 shows the anti-proliferative activity of IFN-alpha2b (Intron A) compared with A02.1 and A10.0 and their corresponding unfused antibodies X02.1 and X10.0 on the multiple myeloma cell line ARP-1. A-isotype is an irrelevant specificity antibody fused with the attenuated interferon as a control. The assay details are described in the Examples (Cell proliferation assay).

FIG. 18 shows the relative fold change of Annexin V production in the CD38-expressing multiple myeloma cell line NCI-H929 when treated with A02.1 and A10.0 and their corresponding unfused antibodies X02.1 and X10.0 for 24 hours compared to an untreated control. A-isotype is an irrelevant specificity antibody fused with the attenuated interferon as a control. The assay details are described in the Examples (Annexin V assay).

FIG. 19 shows the relative fold change of caspase activation in the CD38-expressing multiple myeloma cell line H929 of IFN-alpha2b (Intron A) vs. A02.1 and related constructs in comparison to untreated cells. Isotype 145D is an irrelevant specificity antibody fused with the attenuated interferon as a control. The assay details are described in the Examples (Caspase assay).

FIG. 20 shows the off target activity of IFN-alpha2b (Intron A) versus A02.6 and A02.6 fused to wild-type IFN-alpha2b (A02.6 (wt. IFN)) on the CD38-negative cells. The assay details are described in the Examples (HEK-BLUE™).

FIG. 21 shows the relative fold change of Annexin V production in the CD38-expressing multiple myeloma cell line H929 between IgG1 and IgG4 subtypes of anti-CD38-attenuated IFN-alpha fusion protein constructs. A-isotype is a non-specific IgG4 antibody fused with the attenuated interferon as a control. The antibodies, A02.12 and A10.0 contain IgG4 constant regions fused to attenuated IFN-alpha while A02.112 and A10.59 contain IgG1 constant regions fused to attenuated IFN-alpha. The assay details are described in the Examples (Annexin V/7AAD assay).

FIG. 22 shows the binding activity of A10.0 variants to the CD38-expressing multiple myeloma cell line NCI-H929 as measured by flow cytometry. The assay details are described in the Examples of this specification.

FIG. 23 shows caspase activation in the CD38-expressing multiple myeloma cell line H929 of A10.0 and A10.38 compared to untreated cells. A-isotype is an irrelevant specificity antibody fused to the attenuated IFN as a control. The assay details are described in the Examples (Caspase assay).

FIG. 24 shows the relative fold change of caspase activation in the CD38 expressing multiple myeloma cell line H929 by A10.0 variants compared to untreated cells. The assay details are described in the Examples (Caspase assay).

FIG. 25 shows the relative fold change of production of Annexin V in the CD38-expressing multiple myeloma cell line H929 by A10.0 variants. The assay details are described in the Examples (Annexin V/7AAD assay).

FIG. 26 shows the anti-proliferative activity of IFN-alpha2b (Intron A) compared with A02.6, A10.0, A10.38 and parental A10A2.0 chimeric antibody constructs on the Burkitt's lymphoma cell line Daudi. A-isotype is an irrelevant specificity antibody fused to the attenuated IFN as a control. The assay details are described in the Examples (Cell proliferation assay).

FIG. 27 shows the effects of humanized A10.0 versus the parental A10A2.0 chimeric antibody attenuated interferon construct on the growth of subcutaneous H929 myeloma tumors in SCID mice. The bar labeled “treatment phase” shows the duration of treatment with the compounds.

FIG. 28 shows the non-antibody antigen targeted IFN activity of A10.0 variants fused to the same attenuated IFN-alpha2b protein. The assay details are described in the Examples (“Off-target assays”—iLite gene reporter assay).

FIG. 29 shows the “Off-target” activity of IFN-alpha2b (Intron A) compared with A10.0 variants and the parental A10A2.0 chimeric antibody fused to wild-type IFN-alpha2b (A10A2.0 chimeric (wt.IFN)). The assay details are described in the Examples (“Off-target assays”—HEK-BLUE™).

FIG. 30 shows variable heavy chain consensus sequences of X910/12-HC-L0-Interferon-alpha (A145D) IgG4 and related sequences. Boxed regions contain CDRs (as indicated) as defined by the Kabat numbering system and the enhanced Chothia numbering system. CDRs defined by the Kabat numbering system are shown in bold. CDRs defined by the enhanced Chothia numbering system are underlined.

DETAILED DESCRIPTION OF THE DISCLOSURE

Various terms relating to aspects of disclosure are used throughout the specification and claims. Such terms are to be given their ordinary meaning in the art, unless otherwise indicated. Other specifically defined terms are to be construed in a manner consistent with the definition provided herein.

The terms subject and patient are used interchangeably and include any animal. Mammals are preferred, including companion and farm mammals, as well as rodents, including mice, rabbits, and rats, and other rodents. Non-human primates, such as Cynomolgus monkeys, are more preferred, and human beings are highly preferred.

A molecule such as an antibody has been “isolated” if it has been altered and/or removed from its natural environment by the hand of a human being.

As used herein, the singular forms “a,” “an,” and “the” include plural referents unless expressly stated otherwise.

An anti-CD38 antibody-attenuated interferon alpha-2b fusion construct includes, but is not limited to, any antibody described or exemplified herein that binds specifically to CD38 that is fused to an attenuated interferon alpha-2b protein, including an interferon alpha-2b of SEQ ID NO: 647, SEQ ID NO: 648, SEQ ID NO: 649, SEQ ID NO: 650, or SEQ ID NO: 651. In some aspects, fusing an unmutated interferon alpha-2b protein, such as SEQ ID NO: 7, to an anti-CD38 antibody attenuates the biologic activities of the interferon molecule. In this disclosure, attenuated interferon, attenuated interferon alpha-2b, IFN-alpha2b A145D, and IFN-alpha2b A145G are used interchangeably.

Specificity is not necessarily an absolute designation but may constitute a relative term signifying the degree of selectivity of an antibody IFN-alpha fusion protein construct for an antigen-positive cell compared to an antigen-negative cell. Specificity of an antibody IFN-alpha fusion protein construct for an antigen-positive cell is mediated by the variable regions of the antibody, and usually by the complementarity determining regions (CDRs) of the antibody. A construct may have 100-fold specificity for antigen-positive cells compared to antigen-negative cells.

Human CD38 comprises the amino acid sequence of SEQ ID NO: 1, and cynomolgus monkey CD38 comprises the amino acid sequence of SEQ ID NO: 2.

It has been further observed that interferon-alpha2b can be attenuated in terms of its biologic activity which is mediated through the interferon binding to an interferon receptor on a cell surface by introducing certain amino acid changes into the protein sequence. An attenuated interferon molecule can be fused to antibodies that specifically bind to CD38, such that the antibody may serve as a delivery vehicle for the attenuated interferon to CD38-positive cells with a resulting diminution of off target interferon activity caused by the attenuated interferon molecule. It has been further observed that fusing the attenuated interferon to the CD38 antibodies does not significantly affect the capacity of the antibody to specifically bind to CD38 on cells expressing CD38, including cells in the body of animals. It has been further observed that variants of the CD38 antibodies can be engineered and expressed such that the antibodies have reduced immunogenicity and enhanced stability and half life without a significant loss of specificity or affinity of the antibody to the CD38 antigen. These variant antibodies can be fused to an attenuated interferon.

Accordingly, antibodies that specifically bind to CD38 are featured. It has also been observed that such anti-CD38 antibodies may be employed as delivery vehicles for attenuated ligands such as interferon alpha. Without intending to be limited to any particular theory or mechanism of action, it is believed that the antibodies direct the interferon alpha to which they are attached to CD38-positive cells, where the interferon may interact with its receptor. It is believed that the antibody, as a delivery vehicle, compensates for the diminished capacity of the interferon molecule to bind to its receptor. In this sense, the attenuated interferon has reduced capacity to interact with its receptor on healthy cells, and particularly cells that do not express CD38. It is believed that by bringing the attenuated interferon into proximity with its receptor on CD38-positive cells, the antibodies may enhance the capacity of the attenuated interferon to bind to its relevant receptor and induce a therapeutic effect, while exhibiting a diminished capacity to induce undesirable effects on healthy cells that do not express CD38.

The antibodies may be polyclonal, but in some aspects, are not polyclonal. The antibodies preferably are monoclonal. The antibodies are preferably full length antibodies. Full length antibodies generally comprise a variable region heavy chain and a variable region light chain. The antibodies may comprise derivatives or fragments or portions of antibodies that retain the antigen-binding specificity, and also preferably retain most or all of the affinity, of the parent antibody molecule (e.g., for CD38). For example, derivatives may comprise at least one variable region (either a heavy chain or light chain variable region). Other examples of suitable antibody derivatives and fragments include, without limitation, antibodies with polyepitopic specificity, bispecific antibodies, multi-specific antibodies, diabodies, single-chain molecules, as well as FAb, F(Ab′)2, Fd, Fabc, and Fv molecules, single chain (Sc) antibodies, single chain Fv antibodies (scFv), individual antibody light chains, individual antibody heavy chains, fusions between antibody chains and other molecules, heavy chain monomers or dimers, light chain monomers or dimers, dimers consisting of one heavy and one light chain, and other multimers. Single chain Fv antibodies may be multi-valent. All antibody isotypes may be used to produce antibody derivatives, fragments, and portions. Antibody derivatives, fragments, and/or portions may be recombinantly produced and expressed by any cell type, prokaryotic or eukaryotic.

In some embodiments an isolated antibody may refer to a monoclonal antibody to which IFN-alpha, or an attenuated IFN-alpha, has been fused to the C-terminus of the heavy chain IgG constant region. When the monoclonal antibody has a binding specificity to CD38 and the IFN-alpha is attenuated IFN-alpha 2b, the isolated antibody is also referred to as an Anti-CD38 attenuated IFN-alpha fusion protein, or an Anti-CD38 attenutated IFN-alpha fusion construct herein.

In a full-length antibody, each heavy chain is comprised of a heavy chain variable region (abbreviated herein as HCVR or VH) and a heavy chain constant region. The heavy chain constant region is comprised of three domains, CH1, CH2 and CH3. Each light chain is comprised of a light chain variable region (abbreviated herein as LCVR or VL) and a light chain constant region. The light chain constant region is comprised of one domain, CL. The VH and VL regions can be further subdivided into regions of hypervariability, termed complementarity determining regions (CDR), interspersed with regions that are more conserved, termed framework regions (FWR or FR). Each VH and VL is composed of three CDRs and four FWRs, arranged from amino-terminus to carboxy-terminus in the following order: FWR1, CDR1, FWR2, CDR2, FWR3, CDR3, FWR4. Typically, the antigen binding properties of an antibody are less likely to be disturbed by changes to FWR sequences than by changes to the CDR sequences. Immunoglobulin molecules can be of any type (e.g., IgG, IgE, IgM, IgD, IgA and IgY), class (e.g., IgG1, IgG2, IgG3, IgG4, IgA1 and IgA2) or subclass.

The antibodies may be derived from any species. For example, the antibodies may be mouse, rat, goat, horse, swine, bovine, camel, chicken, rabbit, donkey, llama, dromedary, shark, or human antibodies, as well as antibodies from any other animal species. For use in the treatment of humans, non-human derived antibodies may be structurally altered to be less antigenic upon administration to a human patient, including by chimerization or humanization or superhumanization.

In some aspects, the antibodies are humanized antibodies. Humanized antibodies are those wherein the amino acids directly involved in antigen binding, e.g., the complementarity determining regions (CDR), and in some cases the framework regions (FWR), or portions thereof, of the heavy and/or light chains are not of human origin, while the rest of the amino acids in the antibody are human or otherwise of human origin, e.g., a human antibody scaffold. Humanized antibodies also include antibodies in which one or more residues of the human protein are modified by one or more amino acid substitutions and/or one or more FWR residues of the human protein are replaced by corresponding non-human residues. Humanized antibodies may also comprise residues which are found in neither the human antibody or in the non-human antibody. A humanized antibody may be a super-humanized antibody, e.g., as described in U.S. Pat. No. 7,732,578. The antibodies may be humanized chimeric antibodies.

In highly preferred aspects, the antibodies are fully human. Fully human antibodies are those where the whole molecule is human or otherwise of human origin, or includes an amino acid sequence identical to a human form of the antibody. Fully human antibodies include those obtained from a human V gene library, for example, where human genes encoding variable regions of antibodies are recombinantly expressed. Fully human antibodies may be expressed in other organisms (e.g., mice and xenomouse technology) or cells from other organisms transformed with genes encoding human antibodies. Fully human antibodies may nevertheless include amino acid residues not encoded by human sequences, e.g., mutations introduced by random or site directed mutations.

The antibodies may be full length antibodies of any class, for example, IgG1, IgG2 or IgG4. The constant domains of such antibodies are preferably human. The variable regions of such antibodies may be of non-human origin, or preferably are human in origin or are humanized. Antibody fragments may also be used in place of the full length antibodies.

The antibodies may be minibodies. Minibodies comprise small versions of whole antibodies, which encode in a single chain the essential elements of a whole antibody. For example, the minibody may be comprised of the VH and VL domains of a native antibody fused to the hinge region and CH3 domain of an immunoglobulin molecule.

In some aspects, the antibody may comprise non-immunoglobulin derived protein frameworks. For example, reference may be made to (Ku & Schutz, Proc. Natl. Acad. Sci. USA 92: 6552-6556, 1995) which describes a four-helix bundle protein cytochrome b562 having two loops randomized to create CDRs, which have been selected for antigen binding.

Natural sequence variations may exist among heavy and light chains and the genes encoding them, and therefore, persons having ordinary skill in the art would expect to find some level of variation within the amino acid sequences, or the genes encoding them, of the antibodies described and exemplified herein. These variants preferably maintain the unique binding properties (e.g., specificity and affinity) of the parent antibody. Such an expectation is due in part to the degeneracy of the genetic code, as well as to the known evolutionary success of conservative amino acid sequence variations, which do not appreciably alter the nature of the encoded protein. Accordingly, such variants and homologs are considered substantially the same as one another and are included within the scope of the disclosure. The antibodies thus include variants having single or multiple amino acid substitutions, deletions, additions, or replacements that retain the biological properties (e.g., binding specificity and binding affinity) of the parent antibodies. The variants are preferably conservative, but may be non-conservative.

Amino acid positions assigned to CDRs and FWRs may be defined according to Kabat Sequences of Proteins of Immunological Interest, National Institutes of Health, Bethesda, Md., 1987 and 1991 (also referred to herein as the Kabat numbering system). In addition, the amino acid positions assigned to CDRs and FWRs may be defined according to the Enhanced Chothia Numbering Scheme (www_bioinfo_org_uk/index). The heavy chain constant region of an antibody can be defined by the EU numbering system (Edelman, G M et al. (1969), Proc. Natl. Acad. USA, 63, 78-85).

According to the numbering system of Kabat, VH FWRs and CDRs may be positioned as follows: residues 1-30 (FWR1), 31-35 (CDR1), 36-49 (FWR2), 50-65 (CDR2), 66-94 (FWR3), 95-102 (CDR3) and 103-113 (FWR4), and VL FWRs and CDRs are positioned as follows: residues 1-23 (FWR1), 24-34 (CDR1), 35-49 (FWR2), 50-56 (CDR2), 57-88 (FWR3), 89-97 (CDR3) and 98-107 (FWR4). In some instances, variable regions may increase in length and according to the Kabat numbering system some amino acids may be designated by a number followed by a letter. This specification is not limited to FWRs and CDRs as defined by the Kabat numbering system, but includes all numbering systems, including the canonical numbering system or of Chothia et al. (1987) J. Mol Biol. 196:901-17; Chothia et al. (1989) Nature 342:877-83; and/or Al-Lazikani et al. (1997) J. Mol. Biol. 273:927-48; the numbering system of Honnegher et al. (2001) J. Mol. Biol., 309:657-70; or the IMGT system discussed in Giudicelli et al., (1997) Nucleic Acids Res. 25:206-11. In some aspects, the CDRs are defined according to the Kabat numbering system.

In some particular aspects, for any of the heavy chain CDR2 subdomains described herein, according to the Kabat numbering system, the five C-terminal amino acids may not participate directly in antigen binding, and accordingly, it will be understood that any one or more of these five C-terminal amino acids may be substituted with another naturally-occurring amino acid without substantially adversely affecting antigen binding. In some aspects, for any of the light chain CDR1 subdomains described herein, according to the Kabat numbering system, the four N-terminal amino acids may not participate directly in antigen binding, and accordingly, it will be understood that any one or more of these four amino acids may be substituted with another naturally-occurring amino acid without substantially adversely affecting antigen binding. For example, as described by Padlan et al. (1995) FASEB J. 9:133-139, the five C terminal amino acids of heavy chain CDR2 and/or the four N-terminal amino acids of light chain CDR1 may not participate in antigen binding. In some aspects, both the heavy chain CDR2 and the light chain CDR1 do not directly participate in antigen binding.

In some aspects, chemical analogues of amino acids may be used in the antibodies described and/or exemplified herein. The use of chemical analogues of amino acids is useful, for example, for stabilizing the molecules such as if required to be administered to a subject. The analogues of the amino acids contemplated herein include, but are not limited to, modifications of side chains, incorporation of unnatural amino acids and/or their derivatives during peptide, polypeptide or protein synthesis and the use of crosslinkers and other methods which impose conformational constraints on the proteinaceous molecule or their analogues.

The antibodies may comprise post-translational modifications or moieties, which may impact antibody activity or stability. These modifications or moieties include, but are not limited to, methylated, acetylated, glycosylated, sulfated, phosphorylated, carboxylated, and amidated moieties and other moieties that are well known in the art. Moieties include any chemical group or combinations of groups commonly found on immunoglobulin molecules in nature or otherwise added to antibodies by recombinant expression systems, including prokaryotic and eukaryotic expression systems.

Examples of side chain modifications contemplated by the disclosure include modifications of amino groups such as by reductive alkylation by reaction with an aldehyde followed by reduction with NaBH₄; amidination with methylacetimidate; acylation with acetic anhydride; carbamoylation of amino groups with cyanate; trinitrobenzylation of amino groups with 2, 4, 6-trinitrobenzene sulphonic acid (TNBS); acylation of amino groups with succinic anhydride and tetrahydrophthalic anhydride; and pyridoxylation of lysine with pyridoxal-5-phosphate followed by reduction with NaBH₄.

The guanidine group of arginine residues may be modified by the formation of heterocyclic condensation products with reagents such as 2,3-butanedione, phenylglyoxal and glyoxal.

The carboxyl group may be modified by carbodiimide activation via O-acylisourea formation followed by subsequent derivation, for example, to a corresponding amide.

Sulphydryl groups may be modified by methods such as carboxymethylation with iodoacetic acid or iodoacetamide; performic acid oxidation to cysteic acid; formation of mixed disulphides with other thiol compounds; reaction with maleimide, maleic anhydride or other substituted maleimide; formation of mercurial derivatives using 4-chloromercuribenzoate, 4-chloromercuriphenylsulphonic acid, phenylmercury chloride, 2-chloromercuri-4-nitrophenol and other mercurials; carbamoylation with cyanate at alkaline pH.

Tryptophan residues may be modified by, for example, oxidation with N-bromosuccinimide or alkylation of the indole ring with 2-hydroxy-5-nitrobenzyl bromide or sulphenyl halides. Tyrosine residues on the other hand, may be altered by nitration with tetranitromethane to form a 3-nitrotyrosine derivative.

Modification of the imidazole ring of a histidine residue may be accomplished by alkylation with iodoacetic acid derivatives or N-carbethoxylation with diethylpyrocarbonate.

Crosslinkers may be used, for example, to stabilize 3D conformations of the antibodies and constructs, using homo-bifunctional crosslinkers such as the bifunctionalimido esters having (CH₂)n spacer groups with n=1 to n=6, glutaraldehyde, N-hydroxysuccinimide esters and hetero-bifunctional reagents which usually contain an amino-reactive moiety such as N-hydroxysuccinimide and another group specific-reactive moiety such as maleimido or dithio moiety (SH) or carbodiimide (COOH).

The antibodies may be affinity matured, or may comprise amino acid changes that decrease immunogenicity, for example, by removing predicted MHC class II-binding motifs. The therapeutic utility of the antibodies described herein may be further enhanced by modulating their functional characteristics, such as antibody-dependent cell-mediated cytotoxicity (ADCC), complement-dependent cytotoxicity (CDC), serum half-life, biodistribution and binding to Fc receptors or the combination of any of these. This modulation can be achieved by protein-engineering, glyco-engineering or chemical methods. Depending on the therapeutic application required, it could be advantageous to either increase or decrease any of these activities. An example of glyco-engineering used the Potelligent® method as described in Shinkawa T. et al. (2003) J. Biol. Chem. 278: 3466-73.

The antibodies may include modifications that modulate its serum half-life and biodistribution, including modifications that modulate the antibody's interaction with the neonatal Fc receptor (FcRn), a receptor with a key role in protecting IgG from catabolism, and maintaining high serum antibody concentration. Serum half-life modulating modifications may occur in the Fc region of IgG1 or IgG4, including the triple substitution of M252Y/S254T/T256E (Numbering according to the EU numbering system (Edelman, G. M. et al. (1969) Proc. Natl. Acad. USA 63, 78-85)), (e.g., SEQ ID NO: 656, SEQ ID NO: 657, SEQ ID NO: 658, SEQ ID NO: 694), as described in U.S. Pat. No. 7,083,784. Other substitutions may occur at positions 250 and 428, see e.g., U.S. Pat. No. 7,217,797, as well as at positions 307, 380 and 434, see, e.g., WO 00/42072. Examples of constant domain amino acid substitutions which modulate binding to Fc receptors and subsequent function mediated by these receptors, including FcRn binding and serum half-life, are described in U.S. Publ. Nos. 2009/0142340, 2009/0068175, and 2009/0092599. Naked antibodies may have the heavy chain C-terminal lysine omitted or removed to reduce heterogeneity. The substitution of S228P (EU numbering) in the human IgG4 can stabilize antibody Fab-arm exchange in vivo (Labrin et al. (2009) Nature Biotechnology 27:8; 767-773).

The glycans linked to antibody molecules are known to influence interactions of antibody with Fc receptors and glycan receptors and thereby influence antibody activity, including serum half-life. Hence, certain glycoforms that modulate desired antibody activities can confer therapeutic advantage. Methods for generating engineered glycoforms include but are not limited to those described in U.S. Pat. Nos. 6,602,684, 7,326,681, and 7,388,081 and PCT Publ. No. WO 08/006554. Alternatively, the antibody sequences may be modified to remove relevant glycoform attachment sites.

The antibodies may be labeled or conjugated to any chemical or biomolecule moieties. Labeled antibodies may find use in therapeutic, diagnostic, or basic research applications. Such labels/conjugates can be detectable, such as fluorochromes, radiolabels, enzymes, fluorescent proteins, and biotin. The labels/conjugates may be chemotherapeutic agents, toxins, isotopes, and other agents used for treating conditions such as the killing of cancer cells. Chemotherapeutic agents may be any which is suitable for the purpose to which the antibody is being used.

The antibodies may be derivatized by known protecting/blocking groups to prevent proteolytic cleavage or enhance activity or stability.

The antibodies preferably have a binding affinity for an epitope on CD38 that includes a dissociation constant (Kd) of less than about 1×10⁻² M. In some embodiments, the Kd is less than about 1×10⁻³ M. In other embodiments, the Kd is less than about 1×10⁻⁴M. In some embodiments, the Kd is less than about 1×10⁻⁵ M. In still other embodiments, the Kd is less than about 1×10⁻⁶ M. In other embodiments, the Kd is less than about 1×10⁻⁷M. In other embodiments, the Kd is less than about 1×10⁻⁸ M. In other embodiments, the Kd is less than about 1×10⁻⁹ M. In other embodiments, the Kd is less than about 1×10⁻¹⁰ M. In still other embodiments, the Kd is less than about 1×10⁻¹¹ M. In some embodiments, the Kd is less than about 1×10⁻¹² M. In other embodiments, the Kd is less than about 1×10⁻¹³M. In other embodiments, the Kd is less than about 1×10⁻¹⁴ M. In still other embodiments, the Kd is less than about 1×10⁻¹⁵ M. Affinity values refer to those obtained by standard methodologies, including surface plasmon resonance such as Biacore™ analyses or analysis using an Octet® Red 96 (Forte Bio) Dip-and-Read system.

The antibodies may comprise a single chain Fv molecule (scFv), Fab, or full IgG. Any such antibodies may comprise a heavy chain having an amino acid sequence having at least about 85%, at least about 90%, at least about 95%, at least about 96%, at least about 97%, at least about 98%, at least about 99%, or at least about 100% sequence identity with the amino acid sequence of SEQ ID NO: 659 or SEQ ID NO: 665 or SEQ ID NO: 736, provided that a heavy chain comprising the amino acid sequence of SEQ ID NO: 659 or variant thereof excludes the amino acid sequence of SEQ ID NO: 13. It will be understood that antibodies comprising amino acid changes in their heavy chain retain the capability to specifically bind to CD38. The retained CD38 specific binding activity (including affinity) is preferably about the same as the binding activity (including affinity) of an antibody without any amino acid changes in the heavy chain, although the binding activity (including affinity) may be lesser or greater than an antibody without any amino acid changes in the heavy chain. The antibody may comprise a light chain having an amino acid sequence having at least about 85%, at least about 90%, at least about 95%, at least about 96%, at least about 97%, at least about 98%, at least about 99%, or at least about 100% sequence identity with the amino acid sequence of SEQ ID NO: 664 or SEQ ID NO: 666, provided that a light chain comprising the amino acid sequence of SEQ ID NO: 664 or variant thereof excludes the amino acid sequence of SEQ ID NO: 14. It will be understood that antibodies comprising amino acid changes in their light chain retain the capability to specifically bind to CD38. The retained CD38 specific binding activity (including affinity) is preferably about the same as the binding activity (including affinity) of an antibody without any amino acid changes in the light chain, although the binding activity (including affinity) may be lesser or greater than an antibody without any amino acid changes in the light chain.

In some aspects, the heavy chain FWR1 comprises the amino acid sequence of SEQ ID NO: 199, SEQ ID NO: 206, SEQ ID NO: 214, SEQ ID NO: 215, SEQ ID NO: 217, SEQ ID NO: 219, SEQ ID NO: 389, SEQ ID NO: 396, SEQ ID NO: 400, SEQ ID NO: 404, SEQ ID NO: 408, SEQ ID NO: 412, SEQ ID NO: 416, SEQ ID NO: 420, SEQ ID NO: 424, SEQ ID NO: 428, SEQ ID NO: 432, SEQ ID NO: 466, SEQ ID NO: 470, SEQ ID NO: 472, SEQ ID NO: 474, SEQ ID NO: 476, SEQ ID NO: 478, SEQ ID NO: 480, SEQ ID NO: 482, SEQ ID NO: 486, SEQ ID NO: 488, SEQ ID NO: 513, SEQ ID NO: 537, SEQ ID NO: 542, SEQ ID NO: 547, SEQ ID NO: 552, SEQ ID NO: 557, SEQ ID NO: 562, SEQ ID NO: 567, SEQ ID NO: 572, SEQ ID NO: 577 or SEQ ID NO: 748, and in some aspects, the heavy chain FWR1 comprises an amino acid sequence having at least about 85%, at least about 90%, at least about 92%, at least about 93%, at least about 94%, at least about 95%, at least about 96%, at least about 97%, at least about 98%, or at least about 99% sequence identity with the amino acid sequence of SEQ ID NO: 199, SEQ ID NO: 214, SEQ ID NO: 215, SEQ ID NO: 217, SEQ ID NO: 219, SEQ ID NO: 389, SEQ ID NO: 396, SEQ ID NO: 400, SEQ ID NO: 404, SEQ ID NO: 408, SEQ ID NO: 412, SEQ ID NO: 416, SEQ ID NO: 420, SEQ ID NO: 424, SEQ ID NO: 428, SEQ ID NO: 432, SEQ ID NO: 466, SEQ ID NO: 470, SEQ ID NO: 472, SEQ ID NO: 474, SEQ ID NO: 476, SEQ ID NO: 478, SEQ ID NO: 480, SEQ ID NO: 482, SEQ ID NO: 486, SEQ ID NO: 488, SEQ ID NO: 513, SEQ ID NO: 537, SEQ ID NO: 542, SEQ ID NO: 547, SEQ ID NO: 552, SEQ ID NO: 557, SEQ ID NO: 562, SEQ ID NO: 567, SEQ ID NO: 572, SEQ ID NO: 577 or SEQ ID NO: 748. In some aspects, the heavy chain FWR2 comprises the amino acid sequence of SEQ ID NO: 201, SEQ ID NO: 211, SEQ ID NO: 229, SEQ ID NO: 391, SEQ ID NO: 397, SEQ ID NO: 401, SEQ ID NO: 405, SEQ ID NO: 409, SEQ ID NO: 413, SEQ ID NO: 417, SEQ ID NO: 421, SEQ ID NO: 425, SEQ ID NO: 429, SEQ ID NO: 433, SEQ ID NO: 515, SEQ ID NO: 520, SEQ ID NO: 521, SEQ ID NO: 522, SEQ ID NO: 523, SEQ ID NO: 524, SEQ ID NO: 525, SEQ ID NO: 538, SEQ ID NO: 543, SEQ ID NO: 548, SEQ ID NO: 553, SEQ ID NO: 558, SEQ ID NO: 563, SEQ ID NO: 568, SEQ ID NO: 573, SEQ ID NO: 578, SEQ ID NO: 749 or SEQ ID NO: 750, and in some aspects, the heavy chain FWR2 comprises an amino acid sequence having at least about 85%, at least about 90%, at least about 92%, at least about 93%, at least about 94%, at least about 95%, at least about 96%, at least about 97%, at least about 98%, or at least about 99% sequence identity with the amino acid sequence of SEQ ID NO: 201, SEQ ID NO: 211, SEQ ID NO: 229, SEQ ID NO: 391, SEQ ID NO: 397, SEQ ID NO: 401, SEQ ID NO: 405, SEQ ID NO: 409, SEQ ID NO: 413, SEQ ID NO: 417, SEQ ID NO: 421, SEQ ID NO: 425, SEQ ID NO: 429, SEQ ID NO: 433, SEQ ID NO: 515, SEQ ID NO: 520, SEQ ID NO: 521, SEQ ID NO: 522, SEQ ID NO: 523, SEQ ID NO: 524, SEQ ID NO: 525, SEQ ID NO: 538, SEQ ID NO: 543, SEQ ID NO: 548, SEQ ID NO: 553, SEQ ID NO: 558, SEQ ID NO: 563, SEQ ID NO: 568, SEQ ID NO: 573, SEQ ID NO: 578, SEQ ID NO: 749 or SEQ ID NO: 750. In some aspects, the heavy chain FWR3 comprises the amino acid sequence of SEQ ID NO: 203, SEQ ID NO: 210, SEQ ID NO: 212, SEQ ID NO: 213, SEQ ID NO: 216, SEQ ID NO: 218, SEQ ID NO: 221, SEQ ID NO: 226, SEQ ID NO: 227, SEQ ID NO: 230, SEQ ID NO: 393, SEQ ID NO: 399, SEQ ID NO: 403, SEQ ID NO: 407, SEQ ID NO: 411, SEQ ID NO: 415, SEQ ID NO: 419, SEQ ID NO: 423, SEQ ID NO: 427, SEQ ID NO: 431, SEQ ID NO: 435, SEQ ID NO: 468, SEQ ID NO: 517, SEQ ID NO: 530, SEQ ID NO: 531, SEQ ID NO: 532, SEQ ID NO: 533, SEQ ID NO: 540, SEQ ID NO: 545, SEQ ID NO: 550, SEQ ID NO: 555, SEQ ID NO: 560, SEQ ID NO: 565, SEQ ID NO: 570, SEQ ID NO: 575, SEQ ID NO: 580, SEQ ID NO: 751 or SEQ ID NO: 752 and in some aspects, the heavy chain FWR3 comprises an amino acid sequence having at least about 85%, at least about 90%, at least about 92%, at least about 93%, at least about 94%, at least about 95%, at least about 96%, at least about 97%, at least about 98%, or at least about 99% sequence identity with the amino acid sequence of SEQ ID NO: 203, SEQ ID NO: 210, SEQ ID NO: 212, SEQ ID NO: 213, SEQ ID NO: 216, SEQ ID NO: 218, SEQ ID NO: 221, SEQ ID NO: 226, SEQ ID NO: 227, SEQ ID NO: 230, SEQ ID NO: 393, SEQ ID NO: 399, SEQ ID NO: 403, SEQ ID NO: 407, SEQ ID NO: 411, SEQ ID NO: 415, SEQ ID NO: 419, SEQ ID NO: 423, SEQ ID NO: 427, SEQ ID NO: 431, SEQ ID NO: 435, SEQ ID NO: 468, SEQ ID NO: 517, SEQ ID NO: 530, SEQ ID NO: 531, SEQ ID NO: 532, SEQ ID NO: 533, SEQ ID NO: 540, SEQ ID NO: 545, SEQ ID NO: 550, SEQ ID NO: 555, SEQ ID NO: 560, SEQ ID NO: 565, SEQ ID NO: 570, SEQ ID NO: 575, SEQ ID NO: 580, SEQ ID NO: 751 or SEQ ID NO: 752. In some aspects, the heavy chain FWR4 comprises the amino acid sequence of SEQ ID NO: 205, SEQ ID NO: 395, SEQ ID NO: 519, SEQ ID NO: 541, SEQ ID NO: 546, SEQ ID NO: 551, SEQ ID NO: 556, SEQ ID NO: 561, SEQ ID NO: 566, SEQ ID NO: 571, SEQ ID NO: 576, SEQ ID NO: 581 or SEQ ID NO: 753, and in some aspects, the heavy chain FWR4 comprises an amino acid sequence having at least about 85%, at least about 90%, at least about 92%, at least about 93%, at least about 94%, at least about 95%, at least about 96%, at least about 97%, at least about 98%, or at least about 99% sequence identity with the amino acid sequence of SEQ ID NO: 205, SEQ ID NO: 395, SEQ ID NO: 519, SEQ ID NO: 541, SEQ ID NO: 546, SEQ ID NO: 551, SEQ ID NO: 556, SEQ ID NO: 561, SEQ ID NO: 566, SEQ ID NO: 571, SEQ ID NO: 576, SEQ ID NO: 581 or SEQ ID NO: 753. It will be understood that antibodies comprising amino acid changes in the heavy chain framework region(s) (FWR1, FWR2, FWR3, and/or FWR4) retain the capability to specifically bind to CD38. The retained CD38 specific binding activity (including affinity) is preferably about the same as the binding activity (including affinity) of an antibody without any amino acid changes in any heavy chain framework region(s), although the binding activity (including affinity) may be lesser or greater than an antibody without any amino acid changes in any heavy chain framework region(s).

In some aspects, the heavy chain CDR1 comprises the amino acid sequence of SEQ ID NO: 200, SEQ ID NO: 224, SEQ ID NO: 390, SEQ ID NO: 514, SEQ ID NO: 526, SEQ ID NO: 527, SEQ ID NO: 528, SEQ ID NO: 529, or SEQ ID NO: 697 and in some aspects, the heavy chain CDR1 comprises an amino acid sequence having at least about 85%, at least about 90%, at least about 92%, at least about 93%, at least about 94%, at least about 95%, at least about 96%, at least about 97%, at least about 98%, or at least about 99% sequence identity with the amino acid sequence of SEQ ID NO: 200, SEQ ID NO: 224, SEQ ID NO: 390, SEQ ID NO: 514, SEQ ID NO: 526, SEQ ID NO: 527, SEQ ID NO: 528, SEQ ID NO: 529, or SEQ ID NO: 697. In some aspects, the heavy chain CDR2 comprises the amino acid sequence of SEQ ID NO: 202, SEQ ID NO: 392, SEQ ID NO: 398, SEQ ID NO: 402, SEQ ID NO: 406, SEQ ID NO: 410, SEQ ID NO: 414, SEQ ID NO: 418, SEQ ID NO: 422, SEQ ID NO: 426, SEQ ID NO: 430, SEQ ID NO: 434, SEQ ID NO: 467, SEQ ID NO: 471, SEQ ID NO: 473, SEQ ID NO: 475, SEQ ID NO: 477, SEQ ID NO: 479, SEQ ID NO: 481, SEQ ID NO: 483, SEQ ID NO: 485, SEQ ID NO: 487, SEQ ID NO: 489, SEQ ID NO: 516, SEQ ID NO: 539, SEQ ID NO: 544, SEQ ID NO: 549, SEQ ID NO: 554, SEQ ID NO: 559, SEQ ID NO: 564, SEQ ID NO: 569, SEQ ID NO: 574, SEQ ID NO: 579, SEQ ID NO: 698 or SEQ ID NO: 737 and in some aspects, the heavy chain CDR2 comprises an amino acid sequence having at least about 85%, at least about 90%, at least about 92%, at least about 93%, at least about 94%, at least about 95%, at least about 96%, at least about 97%, at least about 98%, or at least about 99% sequence identity with the amino acid sequence of SEQ ID NO: 202, SEQ ID NO: 392, SEQ ID NO: 398, SEQ ID NO: 402, SEQ ID NO: 406, SEQ ID NO: 410, SEQ ID NO: 414, SEQ ID NO: 418, SEQ ID NO: 422, SEQ ID NO: 426, SEQ ID NO: 430, SEQ ID NO: 434, SEQ ID NO: 467, SEQ ID NO: 471, SEQ ID NO: 473, SEQ ID NO: 475, SEQ ID NO: 477, SEQ ID NO: 479, SEQ ID NO: 481, SEQ ID NO: 483, SEQ ID NO: 485, SEQ ID NO: 487, SEQ ID NO: 489, SEQ ID NO: 516, SEQ ID NO: 539, SEQ ID NO: 544, SEQ ID NO: 549, SEQ ID NO: 554, SEQ ID NO: 559, SEQ ID NO: 564, SEQ ID NO: 569, SEQ ID NO: 574, SEQ ID NO: 579, SEQ ID NO: 698 or SEQ ID NO: 737. In some aspects, the heavy chain CDR3 comprises the amino acid sequence of SEQ ID NO: 204, SEQ ID NO: 220, SEQ ID NO: 222, SEQ ID NO: 223, SEQ ID NO: 228, SEQ ID NO: 231, SEQ ID NO: 394, SEQ ID NO: 469, SEQ ID NO: 518, SEQ ID NO: 534, SEQ ID NO: 535, SEQ ID NO: 536, SEQ ID NO: 699 or SEQ ID NO: 738 and in some aspects, the heavy chain CDR3 comprises an amino acid sequence having at least about 85%, at least about 90%, at least about 92%, at least about 93%, at least about 94%, at least about 95%, at least about 96%, at least about 97%, at least about 98%, or at least about 99% sequence identity with the amino acid sequence of SEQ ID NO: 204, SEQ ID NO: 220, SEQ ID NO: 222, SEQ ID NO: 223, SEQ ID NO: 228, SEQ ID NO: 231, SEQ ID NO: 394, SEQ ID NO: 469, SEQ ID NO: 518, SEQ ID NO: 534, SEQ ID NO: 535, SEQ ID NO: 536, SEQ ID NO: 699 or SEQ ID NO: 738. It will be understood that antibodies comprising amino acid changes in the heavy chain complementarity determining region(s) (CDR1, CDR2, and/or CDR3) retain the capability to specifically bind to CD38. The retained CD38 specific binding activity (including affinity) is preferably about the same as the binding activity (including affinity) of an antibody without any amino acid changes in any heavy chain complementarity determining region(s), although the binding activity (including affinity) may be lesser or greater than an antibody without any amino acid changes in any heavy chain complementarity determining region(s).

In some aspects, the light chain FWR1 comprises the amino acid sequence of SEQ ID NO: 232, SEQ ID NO: 247, SEQ ID NO: 259, SEQ ID NO: 260, SEQ ID NO: 261, SEQ ID NO: 436, SEQ ID NO: 443, SEQ ID NO: 447, SEQ ID NO: 451, SEQ ID NO: 455, SEQ ID NO: 459, SEQ ID NO: 463, SEQ ID NO: 490, SEQ ID NO: 497, SEQ ID NO: 501, SEQ ID NO: 509, SEQ ID NO: 582, SEQ ID NO: 607, SEQ ID NO: 614, SEQ ID NO: 618, SEQ ID NO: 622, SEQ ID NO: 626, SEQ ID NO: 630, SEQ ID NO: 634 or SEQ ID NO: 638 and in some aspects, the light chain FWR1 comprises an amino acid sequence having at least about 85%, at least about 90%, at least about 92%, at least about 93%, at least about 94%, at least about 95%, at least about 96%, at least about 97%, at least about 98%, or at least about 99% sequence identity with the amino acid sequence of SEQ ID NO: 232, SEQ ID NO: 247, SEQ ID NO: 259, SEQ ID NO: 260, SEQ ID NO: 261, SEQ ID NO: 436, SEQ ID NO: 443, SEQ ID NO: 447, SEQ ID NO: 451, SEQ ID NO: 455, SEQ ID NO: 459, SEQ ID NO: 463, SEQ ID NO: 490, SEQ ID NO: 497, SEQ ID NO: 501, SEQ ID NO: 509, SEQ ID NO: 582, SEQ ID NO: 607, SEQ ID NO: 614, SEQ ID NO: 618, SEQ ID NO: 622, SEQ ID NO: 626, SEQ ID NO: 630, SEQ ID NO: 634 or SEQ ID NO: 638. In some aspects, the light chain FWR2 comprises the amino acid sequence of SEQ ID NO: 234, SEQ ID NO: 246, SEQ ID NO: 248, SEQ ID NO: 281, SEQ ID NO: 283, SEQ ID NO: 285, SEQ ID NO: 287, SEQ ID NO: 289, SEQ ID NO: 291, SEQ ID NO: 293, SEQ ID NO: 295, SEQ ID NO: 297, SEQ ID NO: 438, SEQ ID NO: 444, SEQ ID NO: 448, SEQ ID NO: 452, SEQ ID NO: 456, SEQ ID NO: 460, SEQ ID NO: 464, SEQ ID NO: 492, SEQ ID NO: 498, SEQ ID NO: 502, SEQ ID NO: 506, SEQ ID NO: 510, SEQ ID NO: 584, SEQ ID NO: 592, SEQ ID NO: 593, SEQ ID NO: 609, SEQ ID NO: 615, SEQ ID NO: 619, SEQ ID NO: 623, SEQ ID NO: 627, SEQ ID NO: 631, SEQ ID NO: 635 or SEQ ID NO: 639 and in some aspects, the light chain FWR2 comprises an amino acid sequence having at least about 85%, at least about 90%, at least about 92%, at least about 93%, at least about 94%, at least about 95%, at least about 96%, at least about 97%, at least about 98%, or at least about 99% sequence identity with the amino acid sequence of SEQ ID NO: 234, SEQ ID NO: 246, SEQ ID NO: 248, SEQ ID NO: 281, SEQ ID NO: 283, SEQ ID NO: 285, SEQ ID NO: 287, SEQ ID NO: 289, SEQ ID NO: 291, SEQ ID NO: 293, SEQ ID NO: 295, SEQ ID NO: 297, SEQ ID NO: 438, SEQ ID NO: 444, SEQ ID NO: 448, SEQ ID NO: 452, SEQ ID NO: 456, SEQ ID NO: 460, SEQ ID NO: 464, SEQ ID NO: 492, SEQ ID NO: 498, SEQ ID NO: 502, SEQ ID NO: 506, SEQ ID NO: 510, SEQ ID NO: 584, SEQ ID NO: 592, SEQ ID NO: 593, SEQ ID NO: 609, SEQ ID NO: 615, SEQ ID NO: 619, SEQ ID NO: 623, SEQ ID NO: 627, SEQ ID NO: 631, SEQ ID NO: 635 or SEQ ID NO: 639. In some aspects, the light chain FWR3 comprises the amino acid sequence of SEQ ID NO: 236, SEQ ID NO: 245, SEQ ID NO: 265, SEQ ID NO: 266, SEQ ID NO: 267, SEQ ID NO: 271, SEQ ID NO: 272, SEQ ID NO: 274, SEQ ID NO: 276, SEQ ID NO: 277, SEQ ID NO: 278, SEQ ID NO: 279, SEQ ID NO: 280, SEQ ID NO: 282, SEQ ID NO: 284, SEQ ID NO: 286, SEQ ID NO: 288, SEQ ID NO: 290, SEQ ID NO: 292, SEQ ID NO: 294, SEQ ID NO: 296, SEQ ID NO: 298, SEQ ID NO: 300, SEQ ID NO: 302, SEQ ID NO: 304, SEQ ID NO: 306, SEQ ID NO: 308, SEQ ID NO: 310, SEQ ID NO: 312, SEQ ID NO: 314, SEQ ID NO: 316, SEQ ID NO: 318, SEQ ID NO: 320, SEQ ID NO: 323, SEQ ID NO: 327, SEQ ID NO: 331, SEQ ID NO: 335, SEQ ID NO: 339, SEQ ID NO: 343, SEQ ID NO: 347, SEQ ID NO: 351, SEQ ID NO: 355, SEQ ID NO: 359, SEQ ID NO: 363, SEQ ID NO: 367, SEQ ID NO: 371, SEQ ID NO: 375, SEQ ID NO: 379, SEQ ID NO: 383, SEQ ID NO: 387, SEQ ID NO: 440, SEQ ID NO: 445, SEQ ID NO: 449, SEQ ID NO: 453, SEQ ID NO: 457, SEQ ID NO: 461, SEQ ID NO: 465, SEQ ID NO: 494, SEQ ID NO: 499, SEQ ID NO: 503, SEQ ID NO: 507, SEQ ID NO: 511, SEQ ID NO: 586, SEQ ID NO: 611, SEQ ID NO: 616, SEQ ID NO: 620, SEQ ID NO: 624, SEQ ID NO: 628, SEQ ID NO: 632, SEQ ID NO: 636 or SEQ ID NO: 640, and in some aspects, the light chain FWR3 comprises an amino acid sequence having at least about 85%, at least about 90%, at least about 92%, at least about 93%, at least about 94%, at least about 95%, at least about 96%, at least about 97%, at least about 98%, or at least about 99% sequence identity with the amino acid sequence of SEQ ID NO: 236, SEQ ID NO: 245, SEQ ID NO: 265, SEQ ID NO: 266, SEQ ID NO: 267, SEQ ID NO: 271, SEQ ID NO: 272, SEQ ID NO: 274, SEQ ID NO: 276, SEQ ID NO: 277, SEQ ID NO: 278, SEQ ID NO: 279, SEQ ID NO: 280, SEQ ID NO: 282, SEQ ID NO: 284, SEQ ID NO: 286, SEQ ID NO: 288, SEQ ID NO: 290, SEQ ID NO: 292, SEQ ID NO: 294, SEQ ID NO: 296, SEQ ID NO: 298, SEQ ID NO: 300, SEQ ID NO: 302, SEQ ID NO: 304, SEQ ID NO: 306, SEQ ID NO: 308, SEQ ID NO: 310, SEQ ID NO: 312, SEQ ID NO: 314, SEQ ID NO: 316, SEQ ID NO: 318, SEQ ID NO: 320, SEQ ID NO: 323, SEQ ID NO: 327, SEQ ID NO: 331, SEQ ID NO: 335, SEQ ID NO: 339, SEQ ID NO: 343, SEQ ID NO: 347, SEQ ID NO: 351, SEQ ID NO: 355, SEQ ID NO: 359, SEQ ID NO: 363, SEQ ID NO: 367, SEQ ID NO: 371, SEQ ID NO: 375, SEQ ID NO: 379, SEQ ID NO: 383, SEQ ID NO: 387, SEQ ID NO: 440, SEQ ID NO: 445, SEQ ID NO: 449, SEQ ID NO: 453, SEQ ID NO: 457, SEQ ID NO: 461, SEQ ID NO: 465, SEQ ID NO: 494, SEQ ID NO: 499, SEQ ID NO: 503, SEQ ID NO: 507, SEQ ID NO: 511, SEQ ID NO: 586, SEQ ID NO: 611, SEQ ID NO: 616, SEQ ID NO: 620, SEQ ID NO: 624, SEQ ID NO: 628, SEQ ID NO: 632, SEQ ID NO: 636 or SEQ ID NO: 640. In some aspects, the light chain FWR4 comprises the amino acid sequence of SEQ ID NO: 238, SEQ ID NO: 442, SEQ ID NO: 446, SEQ ID NO: 450, SEQ ID NO: 454, SEQ ID NO: 458, SEQ ID NO: 462, SEQ ID NO: 496, SEQ ID NO: 500, SEQ ID NO: 504, SEQ ID NO: 508, SEQ ID NO: 512, SEQ ID NO: 588, SEQ ID NO: 613, SEQ ID NO: 617, SEQ ID NO: 621, SEQ ID NO: 625, SEQ ID NO: 629, SEQ ID NO: 633, SEQ ID NO: 637 or SEQ ID NO: 641 and in some aspects, the light chain FWR4 comprises an amino acid sequence having at least about 85%, at least about 90%, at least about 92%, at least about 93%, at least about 94%, at least about 95%, at least about 96%, at least about 97%, at least about 98%, or at least about 99% sequence identity with the amino acid sequence of SEQ ID NO: 238, SEQ ID NO: 442, SEQ ID NO: 446, SEQ ID NO: 450, SEQ ID NO: 454, SEQ ID NO: 458, SEQ ID NO: 462, SEQ ID NO: 496, SEQ ID NO: 500, SEQ ID NO: 504, SEQ ID NO: 508, SEQ ID NO: 512, SEQ ID NO: 588, SEQ ID NO: 613, SEQ ID NO: 617, SEQ ID NO: 621, SEQ ID NO: 625, SEQ ID NO: 629, SEQ ID NO: 633, SEQ ID NO: 637 or SEQ ID NO: 641. It will be understood that antibodies comprising amino acid changes in the light chain framework region(s) (FWR1, FWR2, FWR3, and/or FWR4) retain the capability to specifically bind to CD38. The retained CD38 specific binding activity (including affinity) is preferably about the same as the binding activity (including affinity) of an antibody without any amino acid changes in any light chain framework region(s), although the binding activity (including affinity) may be lesser or greater than an antibody without any amino acid changes in any light chain framework region(s).

In some aspects, the light chain CDR1 comprises the amino acid sequence of SEQ ID NO: 233, SEQ ID NO: 250, SEQ ID NO: 525, SEQ ID NO: 255, SEQ ID NO: 262, SEQ ID NO: 263, SEQ ID NO: 319, SEQ ID NO: 322, SEQ ID NO: 325, SEQ ID NO: 329, SEQ ID NO: 333, SEQ ID NO: 337, SEQ ID NO: 341, SEQ ID NO: 345, SEQ ID NO: 349, SEQ ID NO: 353, SEQ ID NO: 357, SEQ ID NO: 361, SEQ ID NO: 365, SEQ ID NO: 369, SEQ ID NO: 373, SEQ ID NO: 377, SEQ ID NO: 381, SEQ ID NO: 385, SEQ ID NO: 437, SEQ ID NO: 491, SEQ ID NO: 583, SEQ ID NO: 589, SEQ ID NO: 590, SEQ ID NO: 608, or SEQ ID NO: 696, and in some aspects, the light chain CDR1 comprises an amino acid sequence having at least about 85%, at least about 90%, at least about 92%, at least about 93%, at least about 94%, at least about 95%, at least about 96%, at least about 97%, at least about 98%, or at least about 99% sequence identity with the amino acid sequence of SEQ ID NO: 233, SEQ ID NO: 250, SEQ ID NO: 525, SEQ ID NO: 255, SEQ ID NO: 262, SEQ ID NO: 263, SEQ ID NO: 319, SEQ ID NO: 322, SEQ ID NO: 325, SEQ ID NO: 329, SEQ ID NO: 333, SEQ ID NO: 337, SEQ ID NO: 341, SEQ ID NO: 345, SEQ ID NO: 349, SEQ ID NO: 353, SEQ ID NO: 357, SEQ ID NO: 361, SEQ ID NO: 365, SEQ ID NO: 369, SEQ ID NO: 373, SEQ ID NO: 377, SEQ ID NO: 381, SEQ ID NO: 385, SEQ ID NO: 437, SEQ ID NO: 491, SEQ ID NO: 583, SEQ ID NO: 589, SEQ ID NO: 590, SEQ ID NO: 608, or SEQ ID NO: 696. In some aspects, the light chain CDR2 comprises the amino acid sequence of SEQ ID NO: 235, SEQ ID NO: 249, SEQ ID NO: 253, SEQ ID NO: 264, SEQ ID NO: 299, SEQ ID NO: 301, SEQ ID NO: 303, SEQ ID NO: 305, SEQ ID NO: 307, SEQ ID NO: 309, SEQ ID NO: 311, SEQ ID NO: 313, SEQ ID NO: 315, SEQ ID NO: 317, SEQ ID NO: 326, SEQ ID NO: 330, SEQ ID NO: 334, SEQ ID NO: 338, SEQ ID NO: 342, SEQ ID NO: 346, SEQ ID NO: 350, SEQ ID NO: 354, SEQ ID NO: 358, SEQ ID NO: 362, SEQ ID NO: 366, SEQ ID NO: 370, SEQ ID NO: 374, SEQ ID NO: 378, SEQ ID NO: 382, SEQ ID NO: 386, SEQ ID NO: 439, SEQ ID NO: 493, SEQ ID NO: 585, SEQ ID NO: 591, SEQ ID NO: 605, SEQ ID NO: 610 or SEQ ID NO: 747, and in some aspects, the light chain CDR2 comprises an amino acid sequence having at least about 85%, at least about 90%, at least about 92%, at least about 93%, at least about 94%, at least about 95%, at least about 96%, at least about 97%, at least about 98%, or at least about 99% sequence identity with the amino acid sequence of SEQ ID NO: 235, SEQ ID NO: 249, SEQ ID NO: 253, SEQ ID NO: 264, SEQ ID NO: 299, SEQ ID NO: 301, SEQ ID NO: 303, SEQ ID NO: 305, SEQ ID NO: 307, SEQ ID NO: 309, SEQ ID NO: 311, SEQ ID NO: 313, SEQ ID NO: 315, SEQ ID NO: 317, SEQ ID NO: 326, SEQ ID NO: 330, SEQ ID NO: 334, SEQ ID NO: 338, SEQ ID NO: 342, SEQ ID NO: 346, SEQ ID NO: 350, SEQ ID NO: 354, SEQ ID NO: 358, SEQ ID NO: 362, SEQ ID NO: 366, SEQ ID NO: 370, SEQ ID NO: 374, SEQ ID NO: 378, SEQ ID NO: 382, SEQ ID NO: 386, SEQ ID NO: 439, SEQ ID NO: 493, SEQ ID NO: 585, SEQ ID NO: 591, SEQ ID NO: 605, SEQ ID NO: 610 or SEQ ID NO: 747. In some aspects, the light chain CDR3 comprises the amino acid sequence of SEQ ID NO: 237, SEQ ID NO: 244, SEQ ID NO: 251, SEQ ID NO: 254, SEQ ID NO: 256, SEQ ID NO: 257, SEQ ID NO: 258, SEQ ID NO: 268, SEQ ID NO: 269, SEQ ID NO: 270, SEQ ID NO: 273, SEQ ID NO: 275, SEQ ID NO: 321, SEQ ID NO: 324, SEQ ID NO: 328, SEQ ID NO: 332, SEQ ID NO: 336, SEQ ID NO: 340, SEQ ID NO: 344, SEQ ID NO: 348, SEQ ID NO: 352, SEQ ID NO: 356, SEQ ID NO: 360, SEQ ID NO: 364, SEQ ID NO: 368, SEQ ID NO: 372, SEQ ID NO: 376, SEQ ID NO: 380, SEQ ID NO: 384, SEQ ID NO: 388, SEQ ID NO: 441, SEQ ID NO: 495, SEQ ID NO: 587, SEQ ID NO: 594, SEQ ID NO: 595, SEQ ID NO: 596, SEQ ID NO: 597, SEQ ID NO: 598, SEQ ID NO: 599, SEQ ID NO: 600, SEQ ID NO: 601, SEQ ID NO: 602, SEQ ID NO: 603, SEQ ID NO: 604, SEQ ID NO: 606 or SEQ ID NO: 612, and in some aspects, the light chain CDR3 comprises an amino acid sequence having at least about 85%, at least about 90%, at least about 92%, at least about 93%, at least about 94%, at least about 95%, at least about 96%, at least about 97%, at least about 98%, or at least about 99% sequence identity with the amino acid sequence of SEQ ID NO: 237, SEQ ID NO: 244, SEQ ID NO: 251, SEQ ID NO: 254, SEQ ID NO: 256, SEQ ID NO: 257, SEQ ID NO: 258, SEQ ID NO: 268, SEQ ID NO: 269, SEQ ID NO: 270, SEQ ID NO: 273, SEQ ID NO: 275, SEQ ID NO: 321, SEQ ID NO: 324, SEQ ID NO: 328, SEQ ID NO: 332, SEQ ID NO: 336, SEQ ID NO: 340, SEQ ID NO: 344, SEQ ID NO: 348, SEQ ID NO: 352, SEQ ID NO: 356, SEQ ID NO: 360, SEQ ID NO: 364, SEQ ID NO: 368, SEQ ID NO: 372, SEQ ID NO: 376, SEQ ID NO: 380, SEQ ID NO: 384, SEQ ID NO: 388, SEQ ID NO: 441, SEQ ID NO: 495, SEQ ID NO: 587, SEQ ID NO: 594, SEQ ID NO: 595, SEQ ID NO: 596, SEQ ID NO: 597, SEQ ID NO: 598, SEQ ID NO: 599, SEQ ID NO: 600, SEQ ID NO: 601, SEQ ID NO: 602, SEQ ID NO: 603, SEQ ID NO: 604, SEQ ID NO: 606 or SEQ ID NO: 612. It will be understood that antibodies comprising amino acid changes in the light chain complementarity determining region(s) (CDR1, CDR2, and/or CDR3) retain the capability to specifically bind to CD38. The retained CD38 specific binding activity (including affinity) is preferably about the same as the binding activity (including affinity) of an antibody without any amino acid changes in any light chain complementarity determining region(s), although the binding activity (including affinity) may be lesser or greater than an antibody without any amino acid changes in any light chain complementarity determining region(s).

In some aspects, the antibody comprises particular heavy and light chain pairs. The heavy chains having the amino acid sequences of SEQ ID NO: 659 may be paired with any light chains having the amino acid sequences of SEQ ID NO: 664, or the heavy chains having the amino acid sequences of SEQ ID NO: 665 may be paired with any light chains having the amino acid sequences of SEQ ID NO: 666, or the heavy chain having the amino acid sequences of SEQ ID NO: 736 may be paired with any light chains having the amino acid sequences of SEQ ID NO: 664.

Variable heavy and variable light chain pairs may comprise pairs from the following table:

Variable Heavy Variable Light SEQ ID NO: SEQ ID NO: Antibody Name (amino acid) (amino acid) A02.10 19 14 A02.11 20 14 A02.112 34 65 A02.12 34 65 A02.13 35 65 A02.16 34 92 A02.17 34 93 A02.18 34 73 A02.19 34 74 A02.2 13 65 A02.20 34 75 A02.21 34 76 A02.22 34 77 A02.23 34 78 A02.24 34 79 A02.25 34 80 A02.26 34 81 A02.27 34 82 A02.28 34 83 A02.29 34 84 A02.3 17 65 A02.30 34 85 A02.31 34 86 A02.32 34 87 A02.33 34 88 A02.34 34 89 A02.35 34 90 A02.36 34 91 A02.37 34 66 A02.38 34 113 A02.39 34 112 A02.4 18 65 A02.40 111 65 A02.41 110 65 A02.43 110 113 A02.44 111 112 A02.46 34 67 A02.47 34 68 A02.48 34 69 A02.49 34 70 A02.5 19 65 A02.50 34 71 A02.51 34 72 A02.52 34 94 A02.53 34 95 A02.54 34 96 A02.55 34 97 A02.56 34 98 A02.57 34 99 A02.58 34 100 A02.59 34 101 A02.6 20 65 A02.60 34 102 A02.61 34 103 A02.62 34 104 A02.63 34 105 A02.64 34 106 A02.65 34 107 A02.66 34 108 A02.67 34 109 A02.8 17 14 A02.9 18 14 A10.1 165 161 A10.10 174 161 A10.11 175 161 A10.12 176 161 A10.13 177 161 A10.14 178 161 A10.15 179 161 A10.16 180 161 A10.17 156 181 A10.18 156 182 A10.19 156 183 A10.2 166 161 A10.20 156 184 A10.21 156 185 A10.22 156 186 A10.23 156 187 A10.24 156 188 A10.25 156 189 A10.26 156 190 A10.27 156 191 A10.28 156 192 A10.29 156 193 A10.3 167 161 A10.30 156 194 A10.31 156 195 A10.32 156 196 A10.35 197 161 A10.36 156 198 A10.38 152 161 A10.39 152 181 A10.4 168 161 A10.40 152 182 A10.41 152 183 A10.42 152 184 A10.43 152 185 A10.44 152 186 A10.45 152 187 A10.46 152 188 A10.47 152 189 A10.48 152 190 A10.49 152 191 A10.5 169 161 A10.50 152 192 A10.51 152 193 A10.52 152 194 A10.53 152 195 A10.54 152 196 A10.57 152 198 A10.59 156 161 A10.6 170 161 A10.7 171 161 A10.8 172 161 A10.9 173 161 A10A2.0 (chimeric) 148 157 A10A2.1 149 158 A10A2.10 150 160 A10A2.11 150 161 A10A2.12 150 162 A10A2.13 150 163 A10A2.14 150 164 A10A2.15 151 158 A10A2.16 151 159 A10A2.17 151 160 A10A2.18 151 161 A10A2.19 151 162 A10A2.2 149 159 A10A2.20 151 163 A10A2.21 151 164 A10A2.22 152 158 A10A2.23 152 159 A10A2.24 152 160 A10A2.25 152 161 A10A2.26 152 162 A10A2.27 152 163 A10A2.28 152 164 A10A2.29 153 158 A10A2.3 149 160 A10A2.30 153 159 A10A2.31 153 160 A10A2.32 153 161 A10A2.33 153 162 A10A2.34 153 163 A10A2.35 153 164 A10A2.36 154 158 A10A2.37 154 159 A10A2.38 154 160 A10A2.39 154 161 A10A2.4 149 161 A10A2.40 154 162 A10A2.41 154 163 A10A2.42 154 164 A10A2.43 154 158 A10A2.44 155 159 A10A2.45 155 160 A10A2.46 155 161 A10A2.47 155 162 A10A2.48 155 163 A10A2.49 155 164 A10A2.5 149 162 A10A2.50 156 158 A10A2.51 156 159 A10A2.52 156 160 A10A2.53 156 161 A10A2.54 156 162 A10A2.55 156 163 A10A2.56 156 164 A10A2.6 149 163 A10A2.7 149 164 A10A2.8 150 158 A10A2.9 150 159 A5D1.0 (chimeric) 114 125 A5D1.1 115 126 A5D1.10 116 129 A5D1.11 116 130 A5D1.12 116 131 A5D1.13 117 126 A5D1.14 117 127 A5D1.15 117 128 A5D1.16 117 129 A5D1.17 117 130 A5D1.18 117 131 A5D1.19 118 126 A5D1.2 115 127 A5D1.20 118 127 A5D1.21 118 128 A5D1.22 118 129 A5D1.23 118 130 A5D1.24 118 131 A5D1.25 119 126 A5D1.26 119 127 A5D1.27 119 128 A5D1.28 119 129 A5D1.29 119 130 A5D1.3 115 128 A5D1.30 119 131 A5D1.31 120 126 A5D1.32 120 127 A5D1.33 120 128 A5D1.34 120 129 A5D1.35 120 130 A5D1.36 120 131 A5D1.37 121 126 A5D1.38 121 127 A5D1.39 121 128 A5D1.4 115 129 A5D1.40 121 129 A5D1.41 121 130 A5D1.42 121 131 A5D1.43 122 126 A5D1.44 122 127 A5D1.45 122 128 A5D1.46 122 129 A5D1.47 122 130 A5D1.48 122 131 A5D1.49 123 126 A5D1.5 115 130 A5D1.50 123 127 A5D1.51 123 128 A5D1.52 123 129 A5D1.53 123 130 A5D1.54 123 131 A5D1.55 124 126 A5D1.56 124 127 A5D1.57 124 128 A5D1.58 124 129 A5D1.59 124 130 A5D1.6 115 131 A5D1.60 124 131 A5D1.7 116 126 A5D1.8 116 127 A5D1.9 116 128 A5E8.0 (chimeric) 132 143 A5E8.1 133 144 A5E8.10 135 145 A5E8.11 135 146 A5E8.12 135 147 A5E8.13 136 144 A5E8.14 136 145 A5E8.15 136 146 A5E8.16 136 147 A5E8.17 137 144 A5E8.18 137 145 A5E8.19 137 146 A5E8.2 133 145 A5E8.20 137 147 A5E8.21 138 144 A5E8.22 138 145 A5E8.23 138 146 A5E8.24 138 147 A5E8.25 139 144 A5E8.26 139 145 A5E8.27 139 146 A5E8.28 139 147 A5E8.29 140 144 A5E8.3 133 146 A5E8.30 140 145 A5E8.31 140 146 A5E8.32 140 147 A5E8.33 141 144 A5E8.34 141 145 A5E8.35 141 146 A5E8.36 141 147 A5E8.37 142 144 A5E8.38 142 145 A5E8.39 142 146 A5E8.4 133 147 A5E8.40 142 147 A5E8.5 134 144 A5E8.6 134 145 A5E8.7 134 146 A5E8.8 134 147 A5E8.9 135 144 X02.10 19 14 X02.100 13 58 X02.101 13 59 X02.102 13 60 X02.103 13 61 X02.104 13 62 X02.105 13 63 X02.106 13 64 X02.107 13 65 X02.108 32 14 X02.11 20 14 X02.110 33 14 X02.114 13 660 X02.115 13 661 X02.116 13 662 X02.117 13 663 X02.118 34 700 X02.119 34 701 X02.120 728 700 X02.121 729 700 X02.122 730 700 X02.123 731 700 X02.124 728 701 X02.125 729 701 X02.126 730 701 X02.127 731 701 X02.68 21 14 X02.69 22 14 X02.70 23 14 X02.71 24 14 X02.72 25 14 X02.73 26 14 X02.74 27 14 X02.75 28 14 X02.76 29 14 X02.77 30 14 X02.78 31 14 X02.8 17 14 X02.80 13 38 X02.81 13 39 X02.82 13 40 X02.83 13 41 X02.84 13 42 X02.85 13 43 X02.86 13 44 X02.87 13 45 X02.88 13 46 X02.89 13 47 X02.9 18 14 X02.90 13 48 X02.91 13 49 X02.92 13 50 X02.93 13 51 X02.94 13 52 X02.95 13 53 X02.96 13 54 X02.97 13 55 X02.98 13 56 X02.99 13 57 X10.100 720 706 X10.101 721 706 X10.102 722 706 X10.103 723 706 X10.104 739 706 X10.105 740 706 X10.106 741 706 X10.107 742 706 X10.108 720 707 X10.109 721 707 X10.110 722 707 X10.111 723 707 X10.112 739 707 X10.113 740 707 X10.114 741 707 X10.115 742 707 X10.116 720 708 X10.117 721 708 X10.118 722 708 X10.119 723 708 X10.120 739 708 X10.121 740 708 X10.122 741 708 X10.123 742 708 X10.124 720 709 X10.125 721 709 X10.126 722 709 X10.127 723 709 X10.128 739 709 X10.129 740 709 X10.130 741 709 X10.131 742 709 X10.132 720 710 X10.133 721 710 X10.134 722 710 X10.135 723 710 X10.136 739 710 X10.137 740 710 X10.138 741 710 X10.139 742 710 X10.140 720 711 X10.141 721 711 X10.142 722 711 X10.143 723 711 X10.144 739 711 X10.145 740 711 X10.146 741 711 X10.147 742 711 X10.60 156 704 X10.61 156 705 X10.62 156 706 X10.63 156 707 X10.64 156 708 X10.65 156 709 X10.66 156 710 X10.67 156 711 X10.68 720 161 X10.69 721 161 X10.70 722 161 X10.71 723 161 X10.72 739 161 X10.73 740 161 X10.74 741 161 X10.75 742 161 X10.76 152 704 X10.77 152 705 X10.78 152 706 X10.79 152 707 X10.80 152 708 X10.81 152 709 X10.82 152 710 X10.83 152 711 X10.84 720 704 X10.85 721 704 X10.86 722 704 X10.87 723 704 X10.88 739 704 X10.89 740 704 X10.90 741 704 X10.91 742 704 X10.92 720 705 X10.93 721 705 X10.94 722 705 X10.95 723 705 X10.96 739 705 X10.97 740 705 X10.98 741 705 X10.99 742 705 X910/12-HC-L0- 110 112 IFN-alpha (A145D) IgG4 X913/15-HC-L0- 111 113 IFN-alpha (A145D) IgG4

The antibodies may be fused to attenuated ligands, for example, to form antibody-attenuated ligand constructs, which show an elevated antigen-specificity index with respect to activating signaling pathways due to the action of the attenuated ligand on a cell surface receptor. These constructs are based on the observation that, in the context of an antibody-ligand construct, the ligand portion can be mutated in such a way that the ligand activity on antigen-negative cells is dramatically attenuated, while the ligand activity on antigen-positive cells is only modestly, if at all, attenuated. Such constructs display one, two, three, four or five orders of magnitude greater potency on antigen-positive cells compared to antigen negative cells than does the free ligand. In some aspects, the antibody-attenuated ligand construct retains at least 1%, at least 10%, at least 20%, at least 30%, at least 40% or at least 50% of the potency on antigen-positive cells as the non-attenuated free (i.e., not attached to an antibody) ligand. In some aspects, the antibody-attenuated ligand construct retains at least 30%, at least 50%, at least 75% or at least 90% of the maximal activity of the non-attenuated free (i.e. not attached to an antibody) ligand. Maximal activity includes the amount of signaling activity (or downstream effect thereof) at the high, plateau portion of a dose-response curve, where further increases in the agent does not further increase the amount of response.

In some aspects, the antibody fusion to and inclusion of an attenuating mutation(s) in the interferon ligand increases the antigen-specificity index (ASI) by greater than 10-fold, preferably greater than 50-fold, preferably greater than 100-fold, preferably greater than 1000-fold, or preferably greater than 10,000 fold, relative to an antibody without a fusion. The ASI comprises the fold-increased potency in signaling activity of the antibody-IFN ligand construct relative to the free non-mutated polypeptide ligand on target antigen-positive cells, multiplied by the fold decreased potency in signaling activity relative to the free non-mutated polypeptide ligand on target antigen-negative cells. Potency may be quantitatively represented by the EC₅₀ value, which is the mathematical midpoint of a dose-response curve, in which the dose refers to the concentration of ligand or antibody-ligand construct in an assay, and response refers to the quantitative response of the cells to the signaling activity of the ligand at a particular dose. Thus, for example, when a first compound is shown to possess an EC₅₀ (expressed for example in Molar units) that is 10-fold lower than a second compound's EC₅₀ on the same cells, typically when measured by the same method, the first compound is said to have a 10-fold higher potency. Conversely, when a first compound is shown to possess an EC₅₀ that is 10-fold higher than a second compound's EC₅₀ on the same cells, typically when measured by the same method, the first compound is said to have a 10-fold lower potency.

The antibodies are preferably capable of binding to CD38-positive cells. The antibody may bind to a CD38-positive cell with an EC₅₀ value of less than about 100 nM. The antibody may bind to a CD38-positive cell with an EC₅₀ value of less than about 75 nM. The antibody may bind to a CD38-positive cell with an EC₅₀ value of less than about 50 nM. The antibody may bind to a CD38-positive cell with an EC₅₀ value of less than about 30 nM. The antibody may bind to a CD38-positive cell with an EC₅₀ value of less than about 25 nM. The antibody may bind to a CD38-positive cell with an EC₅₀ value of less than about 20 nM. The antibody may bind to a CD38-positive cell with an EC₅₀ value of less than about 18 nM. The antibody may bind to a CD38-positive cell with an EC₅₀ value of less than about 15 nM. The antibody may bind to a CD38-positive cell with an EC₅₀ value of less than about 13 nM. The antibody may bind to a CD38-positive cell with an EC₅₀ value of less than about 10 nM.

The interferon joined to the antibody preferably comprises alterations in its amino acid sequence, including point mutations and/or deletions that render the interferon less active in stimulating its respective receptors on cells that lack cell surface expression of the CD38 antigen to which the antibody binds. A highly preferred variant of interferon alpha comprises an amino acid change at position 168 of the interferon alpha 2b molecule of SEQ ID NO: 7. For example, the amino acid at position 168, which is an alanine in the parent IFN-alpha2b molecule, is preferably changed to a glycine (Gly/G) (SEQ ID NO: 650) or aspartic acid (Asp/D) (SEQ ID NO: 647). In some aspects, the IFN-alpha2b is truncated at its N-terminus when the IFN-alpha2b is fused to an IgG heavy chain constant domain such as the human IgG1 or human IgG4 heavy chain constant domain. The truncated IFN-alpha2b does not have the twenty three N-terminal amino acids of SEQ ID NO:7 (Met 1 through Gly 23 are deleted), and the truncated IFN-alpha2b comprises the amino acid sequence of SEQ ID NO: 648. The truncated IFN-alpha2b may also comprise the amino acid change at what was formerly position 168, but which becomes position 145 in the truncated protein (e.g., alanine 168 becomes alanine 145). In the truncated IFN-alpha2b, the alanine is preferably changed to a glycine (Gly/G) (SEQ ID NO: 651) or aspartic acid (Asp/D) (SEQ ID NO: 649). Interferon with A145D alteration (SEQ ID NO: 647 or SEQ ID NO: 649) is particularly preferred as the attenuated ligand fused to the antibodies of the disclosure. Any of these point-mutated, attenuated versions of IFN-alpha may be joined to any antibody described herein, for example, as an antibody-attenuated interferon construct.

The linkage between the antibody and the interferon preferably comprises a fusion, for example, a peptide bond between the N- or the C-terminus of the interferon and the N- or C-terminus of the heavy or the light chain of the antibody. In highly preferred aspects, no linker is present between the antibody and the interferon, and the antibody and interferon are thus directly fused. It is believed that direct fusion, without an intervening linker peptide, provides at least a measurable degree of attenuation of the interferon protein, and it is also believed that this attenuation is additive with the attenuation of the interferon protein that stems from the mutations introduced into the interferon protein, including those described or exemplified herein.

Polynucleotide sequences that encode antibodies and their subdomains (e.g., FWRs and CDRs) are featured in the disclosure. Polynucleotides include, but are not limited to, RNA, DNA, cDNA, hybrids of RNA and DNA, and single, double, or triple stranded strands of RNA, DNA, or hybrids thereof.

In some aspects, the polynucleotides encode the heavy chain of an antibody that specifically binds to an epitope on CD38. The polynucleotide may encode a heavy chain comprising the amino acid sequence of any of SEQ ID NO: 667, SEQ ID NO: 668, SEQ ID NO: 679, SEQ ID NO: 680, SEQ ID NO: 681, SEQ ID NO: 682, SEQ ID NO: 683, SEQ ID NO: 684, SEQ ID NO:, SEQ ID NO: 685, SEQ ID NO: 686, SEQ ID NO: 695, SEQ ID NO: 724, SEQ ID NO: 725, SEQ ID NO: 726, SEQ ID NO: 727, SEQ ID NO: 732, SEQ ID NO: 733, SEQ ID NO: 734, SEQ ID NO: 735, SEQ ID NO: 743, SEQ ID NO: 744, SEQ ID NO: 745 or SEQ ID NO: 746. The polynucleotide may encode a light chain comprising the amino acid sequence of any of SEQ ID NO: 669, SEQ ID NO: 670, SEQ ID NO: 671, SEQ ID NO: 672, SEQ ID NO: 673, SEQ ID NO: 674, SEQ ID NO: 675, SEQ ID NO: 676, SEQ ID NO: 677, SEQ ID NO: 678, SEQ ID NO: 688, SEQ ID NO: 689, SEQ ID NO: 690, SEQ ID NO: 691, SEQ ID NO: 692, SEQ ID NO: 693, SEQ ID NO: 702, SEQ ID NO: 703, SEQ ID NO: 712, SEQ ID NO: 713, SEQ ID NO: 714, SEQ ID NO: 715, SEQ ID NO: 716, SEQ ID NO: 717, SEQ ID NO: 718 or SEQ ID NO: 719. The polynucleotide may comprise the nucleic acid sequence of any of SEQ ID NO: 667, SEQ ID NO: 668, SEQ ID NO: 679, SEQ ID NO: 680, SEQ ID NO: 681, SEQ ID NO: 682, SEQ ID NO: 683, SEQ ID NO: 684, SEQ ID NO:, SEQ ID NO: 685, SEQ ID NO: 686, SEQ ID NO:695, SEQ ID NO: 724, SEQ ID NO: 725, SEQ ID NO: 726, SEQ ID NO: 727, SEQ ID NO: 732, SEQ ID NO: 733, SEQ ID NO: 734, SEQ ID NO: 735, SEQ ID NO: 743, SEQ ID NO: 744, SEQ ID NO: 745, SEQ ID NO: 746, SEQ ID NO: 669, SEQ ID NO: 670, SEQ ID NO: 671, SEQ ID NO: 672, SEQ ID NO: 673, SEQ ID NO: 674, SEQ ID NO: 675, SEQ ID NO: 676, SEQ ID NO: 677, SEQ ID NO: 678, SEQ ID NO: 688, SEQ ID NO: 689, SEQ ID NO: 690, SEQ ID NO: 691, SEQ ID NO: 692, SEQ ID NO: 693, SEQ ID NO: 702, SEQ ID NO: 703, SEQ ID NO: 712, SEQ ID NO: 713, SEQ ID NO: 714, SEQ ID NO: 715, SEQ ID NO: 716, SEQ ID NO: 717, SEQ ID NO: 718 or SEQ ID NO: 719. The polynucleotide may comprise a nucleic acid sequence having at least about 80%, at least about 85%, at least about 86%, at least about 87%, at least about 88%, at least about 89%, at least about 90%, at least about 91%, at least about 92%, at least about 93%, at least about 94%, at least about 95%, at least about 96%, at least about 97%, at least about 98%, or at least about 99% sequence identity with any of SEQ ID NO: 667, SEQ ID NO: 668, SEQ ID NO: 679, SEQ ID NO: 680, SEQ ID NO: 681, SEQ ID NO: 682, SEQ ID NO: 683, SEQ ID NO: 684, SEQ ID NO:, SEQ ID NO: 685, SEQ ID NO: 686, SEQ ID NO:695, SEQ ID NO: 724, SEQ ID NO: 725, SEQ ID NO: 726, SEQ ID NO: 727, SEQ ID NO: 732, SEQ ID NO: 733, SEQ ID NO: 734, SEQ ID NO: 735, SEQ ID NO: 743, SEQ ID NO: 744, SEQ ID NO: 745, SEQ ID NO: 746, SEQ ID NO: 669, SEQ ID NO: 670, SEQ ID NO: 671, SEQ ID NO: 672, SEQ ID NO: 673, SEQ ID NO: 674, SEQ ID NO: 675, SEQ ID NO: 676, SEQ ID NO: 677, SEQ ID NO: 678, SEQ ID NO: 688, SEQ ID NO: 689, SEQ ID NO: 690, SEQ ID NO: 691, SEQ ID NO: 692, SEQ ID NO: 693, SEQ ID NO: 702, SEQ ID NO: 703, SEQ ID NO: 712, SEQ ID NO: 713, SEQ ID NO: 714, SEQ ID NO: 715, SEQ ID NO: 716, SEQ ID NO: 717, SEQ ID NO: 718 or SEQ ID NO: 719, and in some aspects such variants preferably encode the same amino acids encoded by the polynucleotide sequence of SEQ ID NO: 667, SEQ ID NO: 668, SEQ ID NO: 679, SEQ ID NO: 680, SEQ ID NO: 681, SEQ ID NO: 682, SEQ ID NO: 683, SEQ ID NO: 684, SEQ ID NO:, SEQ ID NO: 685, SEQ ID NO: 686, SEQ ID NO:695, SEQ ID NO: 724, SEQ ID NO: 725, SEQ ID NO: 726, SEQ ID NO: 727, SEQ ID NO: 732, SEQ ID NO: 733, SEQ ID NO: 734, SEQ ID NO: 735, SEQ ID NO: 743, SEQ ID NO: 744, SEQ ID NO: 745, SEQ ID NO: 746, SEQ ID NO: 669, SEQ ID NO: 670, SEQ ID NO: 671, SEQ ID NO: 672, SEQ ID NO: 673, SEQ ID NO: 674, SEQ ID NO: 675, SEQ ID NO: 676, SEQ ID NO: 677, SEQ ID NO: 678, SEQ ID NO: 688, SEQ ID NO: 689, SEQ ID NO: 690, SEQ ID NO: 691, SEQ ID NO: 692, SEQ ID NO: 693, SEQ ID NO: 702, SEQ ID NO: 703, SEQ ID NO: 712, SEQ ID NO: 713, SEQ ID NO: 714, SEQ ID NO: 715, SEQ ID NO: 716, SEQ ID NO: 717, SEQ ID NO: 718 or SEQ ID NO: 719. Preferably, the antibodies encoded by the polynucleotide variants will specifically bind to CD38 with an affinity about equal to the affinity of the antibody encoded by the parent (non-variant) polynucleotide sequence. Affinity may be measured, for example, according to any technique described or exemplified herein, including techniques described in the Examples. Complements of the polynucleotide sequences and the variant polynucleotide sequences are also within the scope of the disclosure.

Also encompassed within the disclosure are vectors comprising the polynucleotides of the disclosure. The vectors may be expression vectors. Recombinant expression vectors containing a sequence encoding a polypeptide of interest are thus provided. The expression vector may contain one or more additional sequences, such as but not limited to regulatory sequences, a selection marker, a purification tag, or a polyadenylation signal. Such regulatory elements may include a transcriptional promoter, enhancers, mRNA ribosomal binding sites, or sequences that control the termination of transcription and translation.

Expression vectors, especially mammalian expression vectors, may include one or more nontranscribed elements, such as an origin of replication, a suitable promoter and enhancer linked to the gene to be expressed, other 5′ or 3′ flanking nontranscribed sequences, 5′ or 3′ nontranslated sequences (such as necessary ribosome binding sites), a polyadenylation site, splice donor and acceptor sites, or transcriptional termination sequences. An origin of replication that confers the ability to replicate in a specific host may also be incorporated.

The vectors may be used to transform any of a wide array of host cells well known to those of skill in the art, and preferably host cells capable of expressing antibodies. Vectors include without limitation, plasmids, phagemids, cosmids, baculoviruses, bacmids, bacterial artificial chromosomes (BACs), yeast artificial chromosomes (YACs), and baculovirus, as well as other bacterial, eukaryotic, yeast, and viral vectors. Suitable host cells include without limitation CHO cells, HEK293 cells, or any eukaryotic stable cell line known or produced, and also include bacteria, yeast, and insect cells.

The antibodies may also be produced by hybridoma cells; methods to produce hybridomas being well known and established in the art.

It has been observed in accordance with the disclosure that when interferon alpha ligand, having one or more mutations that substantially decrease the affinity of the ligand for an interferon receptor, is linked to an anti-CD38 antibody that targets the mutated interferon alpha ligand to target cells which display the antibody's corresponding antigen, the ligand's activity on target antigen-positive cells is maintained while the ligand's activity on non-target antigen-negative cells is substantially reduced. The net result is a ligand signaling molecule that has a much greater potency in activation of its receptors on antigen-positive target cells compared to antigen-negative non-target cells, which provides a means for reducing toxicity arising from off-target ligand activity.

In some aspects, a polypeptide construct comprises an IFN-alpha variant linked to an anti-CD38 antibody or antigen binding portion thereof. Such a polypeptide will be capable of exerting with high potency the IFN's anti-proliferative activity on CD38-positive tumor cells while exerting a much lower potency on CD38-negative, non-tumor cells within the body.

The disclosure also provides compositions comprising the antibodies and antibody-attenuated interferon constructs of the disclosure. These compositions can further comprise at least one of any suitable auxiliary, such as, but not limited to one or more, diluents, binders, stabilizers, buffers, salts, lipophilic solvents, preservatives, adjuvants, or other suitable carrier and/or excipient. Pharmaceutically acceptable auxiliaries are preferred. The compositions may comprise any of the antibodies and antibody-attenuated interferon constructs described and/or exemplified herein and an acceptable carrier such as a pharmaceutically acceptable carrier. Suitable carriers include any media that does not interfere with the biological activity of the antibody and/or the interferon and preferably is not toxic to a host to which it is administered. The carrier may be an aqueous solution, such as water, saline, or alcohol, or a physiologically compatible buffer, such as Hanks's solution, Ringer's solution, or physiological saline buffer. The carrier may contain formulatory agents, such as suspending, stabilizing and/or dispersing agents

Pharmaceutical excipients and additives useful in the composition include but are not limited to proteins, peptides, amino acids, lipids, and carbohydrates (e.g., sugars, including monosaccharides, di-, tri-, tetra-, and oligosaccharides; derivatized sugars such as alditols, aldonic acids, esterified sugars and other known sugars; and polysaccharides or sugar polymers), which can be present singly or in combination, comprising alone or in combination any suitable weight or volume. Exemplary protein excipients include serum albumin, such as human serum albumin (HSA), recombinant human albumin (rHA), gelatin, casein, and other known proteins. Representative amino acids which can also function in a buffering capacity include alanine, glycine, arginine, betaine, histidine, glutamic acid, aspartic acid, cysteine, lysine, leucine, isoleucine, valine, methionine, phenylalanine, and aspartame. One preferred amino acid is histidine. A second preferred amino acid is arginine.

Carbohydrate excipients suitable for use in the composition include, for example, monosaccharides, such as fructose, maltose, galactose, glucose, D-mannose, and sorbose; disaccharides, such as lactose, sucrose, trehalose, and cellobiose; polysaccharides, such as raffinose, melezitose, maltodextrins, dextrans, and starches; and alditols, such as mannitol, xylitol, maltitol, lactitol, xylitol sorbitol (glucitol), and myoinositol. Preferred carbohydrate excipients for use in the disclosure are mannitol, trehalose, and raffinose.

Antibody compositions can also include a buffer or a pH adjusting agent; typically, the buffer is a salt prepared from an organic acid or base. Representative buffers include organic acid salts, such as salts of citric acid, ascorbic acid, gluconic acid, carbonic acid, tartaric acid, succinic acid, acetic acid, or phthalic acid; Tris, tromethamine hydrochloride, or phosphate buffers. Preferred buffers for use in the present compositions are organic acid salts, such as citrate.

Additionally, the compositions of the disclosure can include polymeric excipients/additives, such as polyvinylpyrrolidones, ficolls (a polymeric sugar), dextrates (e.g., cyclodextrins, such as 2-hydroxypropyl-β-cyclodextrin), polyethylene glycols, antimicrobial agents, antioxidants, antistatic agents, surfactants (e.g., polysorbates such as “TWEEN® 20” and “TWEEN® 80”), lipids (e.g., phospholipids, fatty acids), steroids (e.g., cholesterol), and chelating agents (e.g., EDTA).

The compositions may also be formulated in sustained release vehicles or depot preparations. For example, the compositions may be formulated with suitable polymeric or hydrophobic materials (for example, as an emulsion in an acceptable oil) or ion exchange resins, or as sparingly soluble derivatives, for example, as a sparingly soluble salt. Liposomes and emulsions are well-known examples of delivery vehicles suitable for use as carriers for hydrophobic drugs.

The compositions may be formulated for administration to a subject in any suitable dosage form. The compositions may be formulated for oral, buccal, nasal, transdermal, parenteral, injectable, intravenous, subcutaneous, intramuscular, rectal, or vaginal administrations. The compositions may be formulated in a suitable controlled-release vehicle, with an adjuvant, or as a depot formulation.

Preparations for parenteral administration include sterile solutions ready for injection, sterile dry soluble products ready to be combined with a solvent just prior to use, including hypodermic tablets, sterile suspensions ready for injection, sterile dry insoluble products ready to be combined with a vehicle just prior to use and sterile emulsions.

An anti-CD38-attenuated interferon alpha-2b fusion construct may be used, for example, to inhibit, reduce, decrease, block, or prevent proliferation of a cell that expressed CD38 on its surface. In some aspects, methods for inhibiting or reducing proliferation of a cell that expresses CD38 on its surface generally comprise contacting a cell expressing CD38 with an anti-CD38-attenuated interferon alpha-2b fusion construct in an amount effective to inhibit or reduce proliferation of the cell. The antibody that specifically binds to CD38 may be any antibody described or exemplified herein. The attenuated interferon alpha 2b may comprise IFN-alpha2b A145D or IFN-alpha2b A145G. The cell may be a lymphocyte, an autoimmune lymphocyte, or a tumor cell such as a leukemia cell, a multiple myeloma cell, or a lymphoma cell. The anti-CD38-attenuated interferon alpha-2b fusion construct may be comprised in a composition, for example, with a pharmaceutically acceptable carrier and optionally one or more auxiliaries or excipients, including any such carrier, auxiliary, or excipient described or exemplified herein. The methods may be carried out in vitro, ex vivo, in vivo, or in situ.

An anti-CD38-attenuated interferon alpha-2b fusion construct may also be used, for example, to induce, facilitate, or enhance apoptosis of a cell that expressed CD38 on its surface. In some aspects, methods for inducing apoptosis in a cell that expresses CD38 on its surface generally comprise contacting a cell expressing CD38 with an anti-CD38-attenuated interferon alpha-2b fusion construct in an amount effective to induce apoptosis in the cell. The antibody that specifically binds to CD38 may be any antibody described or exemplified herein. The attenuated interferon alpha 2b may comprise IFN-alpha2b A145D or IFN-alpha2b A145G. The cell may be a lymphocyte, an autoimmune lymphocyte, or a tumor cell such as a leukemia cell, a multiple myeloma cell, or a lymphoma cell. The anti-CD38-attenuated interferon alpha-2b fusion construct may be comprised in a composition, for example, with a pharmaceutically acceptable carrier and optionally one or more auxiliaries or excipients, including any such carrier, auxiliary, or excipient described or exemplified herein. The methods may be carried out in vitro, ex vivo, in vivo, or in situ.

An anti-CD38-attenuated interferon alpha-2b fusion construct may also be used to treat a subject having a tumor that comprises and/or is mediated, at least in part, by cells that express CD38 on their surface. In some aspects, methods for treating a tumor comprising cells expressing CD38 on their surface generally comprise administering to a subject in need thereof an anti-CD38-attenuated interferon alpha-2b fusion construct in an amount effective to treat the tumor in the subject. Effective treatment may include, for example, inhibiting or reducing proliferation of CD38-positive cells in the tumor and/or inducing apoptosis of CD38-positive cells in the tumor. The antibody that specifically binds to CD38 may be any antibody described or exemplified herein. The attenuated interferon alpha 2b may comprise IFN-alpha2b A145D or IFN-alpha2b A145G. The anti-CD38-attenuated interferon alpha-2b fusion construct may be comprised in a composition, for example, with a pharmaceutically acceptable carrier and optionally one or more auxiliaries or excipients, including any such carrier, auxiliary, or excipient described or exemplified herein.

The anti-CD38-attenuated interferon alpha-2b fusion constructs or composition comprising such constructs may be administered to the tumor by administering the constructs of composition to the blood. The anti-CD38-attenuated interferon alpha-2b fusion constructs or composition comprising such constructs may be administered such that the construct diffuses via blood flow to and/or into the tumor cells. The construct may be internalized by a tumor cell.

Use of an anti-CD38 antibody or anti-CD38 antibody-attenuated interferon alpha-2b fusion construct in the treatment of tumors are provided. Methods for treating tumors with an anti-CD38 antibody or anti-CD38 antibody-attenuated interferon alpha-2b fusion construct are provided. Any anti-CD38 antibody or anti-CD38 antibody-attenuated interferon alpha-2b fusion construct described or exemplified herein may be used. Tumors that may be treated include, but are not limited to AIDS related cancers, acoustic neuroma, acute lymphocytic leukemia, acute myeloid leukemia, adenocystic carcinoma, adrenocortical cancer, agnogenic myeloid metaplasia, alopecia, alveolar soft-part sarcoma, anal cancer, angiosarcoma, aplastic anemia, astrocytoma, ataxia-telangiectasia, basal cell carcinoma (skin), bladder cancer, bone cancers, bowel cancer, brain stem glioma, brain and CNS tumors, breast cancer, CNS tumors, carcinoid tumors, cervical cancer, childhood brain tumors, childhood cancer, childhood leukemia, childhood soft tissue sarcoma, chondrosarcoma, choriocarcinoma, chronic lymphocytic leukemia, chronic myeloid leukemia, colorectal cancers, cutaneous T-Cell lymphoma, dermatofibrosarcoma-protuberans, desmoplastic-small-round-cell-tumor, ductal carcinoma, endocrine cancers, endometrial cancer, ependymoma, esophageal cancer, Ewing's sarcoma, extra-hepatic bile duct cancer, eye cancer, eye: melanoma, retinoblastoma, fallopian tube cancer, fanconi anemia, fibrosarcoma, gall bladder cancer, gastric cancer, gastrointestinal cancers, gastrointestinal-carcinoid-tumor, genitourinary cancers, germ cell tumors, gestational-trophoblastic-disease, glioma, gynecological cancers, hematological malignancies, hairy cell leukemia, head and neck cancer, hepatocellular cancer, hereditary breast cancer, histiocytosis, Hodgkin's disease, human papillomavirus, hydatidiform mole, hypercalcemia, hypopharynx cancer, intraocular melanoma, islet cell cancer, Kaposi's sarcoma, kidney cancer, Langerhan's-cell-histiocytosis, laryngeal cancer, leiomyosarcoma, leukemia, Li-Fraumeni syndrome, lip cancer, liposarcoma, liver cancer, lung cancer, lymphedema, lymphoma, Hodgkin's lymphoma, non-Hodgkin's lymphoma, male breast cancer, malignant-rhabdoid-tumor-of-kidney, medulloblastoma, melanoma, merkel cell cancer, mesothelioma, metastatic cancer, mouth cancer, multiple endocrine neoplasia, mycosis fungoides, myelodysplastic syndromes, multiple myeloma, myeloproliferative disorders, nasal cancer, nasopharyngeal cancer, nephroblastoma, neuroblastoma, neurofibromatosis, nijmegen breakage syndrome, non-melanoma skin cancer, non-small-cell-lung-cancer-(NSCLC), ocular cancers, esophageal cancer, oral cavity cancer, oropharynx cancer, osteosarcoma, ostomy ovarian cancer, pancreas cancer, paranasal cancer, parathyroid cancer, parotid gland cancer, penile cancer, peripheral-neuroectodermal-tumors, pituitary cancer, polycythemia vera, prostate cancer, rare-cancers-and-associated-disorders, renal cell carcinoma, retinoblastoma, rhabdomyosarcoma, Rothmund-Thomson syndrome, salivary gland cancer, sarcoma, schwannoma, Sezary syndrome, skin cancer, small cell lung cancer (SCLC), small intestine cancer, soft tissue sarcoma, spinal cord tumors, squamous-cell-carcinoma-(skin), stomach cancer, synovial sarcoma, testicular cancer, thymus cancer, thyroid cancer, transitional-cell-cancer-(bladder), transitional-cell-cancer-(renal-pelvis-/-ureter), trophoblastic cancer, urethral cancer, urinary system cancer, uroplakins, uterine sarcoma, uterus cancer, vaginal cancer, vulva cancer, Waldenstrom's-macroglobulinemia and Wilms' tumor. In an embodiment the tumor is selected from a group of multiple myeloma or non-hodgkin's lymphoma.

In preferred aspects, the methods are used for treatment of multiple myeloma, leukemia, or lymphoma in a subject in need thereof. Such methods may further comprise treating the subject with a retinoid, such as all-trans retinoic acid. In some preferred aspects in which the cell surface associated antigen is CD38, the tumor or cancer may be selected from multiple myeloma, non-Hodgkin's lymphoma, chronic myelogenous leukemia, chronic lymphocytic leukemia or acute myelogenous leukemia.

An anti-CD38-attenuated interferon alpha-2b fusion construct may be combined with other drugs and/or used in addition to other cancer treatment regimens or modalities such as radiation therapy or surgery. When anti-CD38-attenuated interferon alpha-2b fusion constructs are used in combination with known therapeutic agents the combination may be administered either in sequence (either continuously or broken up by periods of no treatment) or concurrently or as a mixture. In the case of cancer, there are numerous known anticancer agents that may be used in this context. Treatment in combination is also contemplated to encompass the treatment with either the anti-CD38-attenuated interferon alpha-2b fusion construct followed by a known treatment, or treatment with a known agent followed by treatment with the anti-CD38-attenuated interferon alpha-2b fusion construct, for example, as maintenance therapy. For example, in the treatment of cancer it is contemplated that the anti-CD38-attenuated interferon alpha-2b fusion construct may be administered in combination with an alkylating agent (such as mechlorethamine, cyclophosphamide, chlorambucil, ifosfamidecysplatin, or platinum-containing alkylating-like agents such as cisplatin, carboplatin and oxaliplatin), an antimetabolite (such as a purine or pyrimidine analogue or an antifolate agent, such as azathioprine and mercaptopurine), an anthracycline (such as Daunorubicin, Doxorubicin, Epirubicinldarubicin, Valrubicin, Mitoxantrone, or anthracycline analog), a plant alkaloid (such as a vinca alkaloid or a taxane, such as Vincristine, Vinblastine, Vinorelbine, Vindesine, paclitaxel or Dosetaxel), a topoisomerase inhibitor (such as a type I or type II topoisomerase inhibitor), a Podophyllotoxin (such as etoposide or teniposide), or a tyrosine kinase inhibitor (such as imatinibmesylate, Nilotinib, or Dasatinib).

In the case of the treatment of multiple myeloma, an anti-CD38-attenuated interferon alpha-2b fusion construct may be administered in combination with other suitable therapies, such as treatment of the subject with the administration of steroids such as dexamethasone, proteasome inhibitors (such as bortezomib or carfilzomib), immunomodulatory drugs (such as thalidomide, lenalidomide or pomalidomide), or induction chemotherapy followed by autologous hematopoietic stem cell transplantation, with or without other chemotherapeutic agents such as Melphalan hydrochloride or the chemotherapeutic agents listed above.

In the case of the treatment of Hodgkin's lymphoma, an anti-CD38-attenuated interferon alpha-2b fusion construct may be administered in combination with current therapeutic approaches, such as ABVD (Adriamycin (doxorubicin), bleomycin, vinblastine, and dacarbazine), or Stanford V (doxorubicin, bleomycin, vinblastine, vincristine, mechlorethamine, etoposide, prednisone), or BEACOPP (doxorubicin, bleomycin, vincristine, cyclophosphamide, procarbazine, etoposide, prednisone).

In the case of non-Hodgkin's lymphoma or other lymphomas, an anti-CD38-attenuated interferon alpha-2b fusion construct may be administered in combination current therapeutic approaches. Examples of drugs approved for non-Hodgkin lymphoma include Abitrexate (Methotrexate), Adriamycin PFS (Doxorubicin Hydrochloride), Adriamycin RDF (Doxorubicin Hydrochloride), Ambochlorin (Chlorambucil), Amboclorin (Chlorambucil), Arranon (Nelarabine), Bendamustine Hydrochloride, Bexxar (Tositumomab and Iodine I 131 Tositumomab), Blenoxane (Bleomycin), Bleomycin, Bortezomib, Chlorambucil, Clafen (Cyclophosphamide), Cyclophosphamide, Cytoxan (Cyclophosphamide), DenileukinDiftitox, DepoCyt (Liposomal Cytarabine), Doxorubicin Hydrochloride, DTIC-Dome (Dacarbazine), Folex (Methotrexate), Folex PFS (Methotrexate), Folotyn (Pralatrexate), IbritumomabTiuxetan, Istodax (Romidepsin), Leukeran (Chlorambucil), Linfolizin (Chlorambucil), Liposomal Cytarabine, Matulane (Procarbazine Hydrochloride), Methotrexate, Methotrexate LPF (Methotrexate), Mexate (Methotrexate), Mexate-AQ (Methotrexate), Mozobil (Plerixafor), Nelarabine, Neosar (Cyclophosphamide), Ontak (DenileukinDiftitox), Plerixafor, Pralatrexate, Rituxan (Rituximab), Rituximab, Romidepsin, Tositumomab and Iodine I 131 Tositumomab, Treanda (Bendamustine Hydrochloride), Velban (Vinblastine Sulfate), Velcade (Bortezomib), and Velsar (Vinblastine Sulfate), Vinblastine Sulfate, Vincasar PFS (Vincristine Sulfate), Vincristine Sulfate, Vorinostat, Zevalin (IbritumomabTiuxetan), Zolinza (Vorinostat). Examples of drug combinations used in treating non-Hodgkin lymphoma include CHOP (C=Cyclophosphamide, H=Doxorubicin Hydrochloride (Hydroxydaunomycin), O=Vincristine Sulfate (Oncovin), P=Prednisone); COPP (C=Cyclophosphamide, O=Vincristine Sulfate (Oncovin), P=Procarbazine Hydrochloride, P=Prednisone); CVP (C=Cyclophosphamide, V=Vincristine Sulfate, P=Prednisone); EPOCH (E=Etoposide, P=Prednisone, O=Vincristine Sulfate (Oncovin), C=Cyclophosphamide, H=Doxorubicin Hydrochloride (Hydroxydaunomycin)); ICE (I=Ifosfamide, C=Carboplatin, E=Etoposide) and R-CHOP (R=Rituximab, C=Cyclophosphamide, H=Doxorubicin Hydrochloride (Hydroxydaunomycin), O=Vincristine Sulfate (Oncovin), P=Prednisone.

An anti-CD38 antibody, or an anti-CD38-attenuated interferon alpha-2b fusion construct may be used to detect CD38-positive cells, including CD38-positive tumor cells. In some aspects, they may be used in methods for detecting a CD38-positive tumor cell in a tissue sample isolated from a subject, which methods may generally comprise contacting an anti-CD38 antibody, or an anti-CD38-attenuated interferon alpha-2b fusion construct, with a tissue sample isolated from a subject and detecting a complex of the antibody or construct and a CD38-positive cell in the tissue sample. The tissue sample preferably is blood. The cell may be a CD38-positive B-cell lymphoma cell, multiple myeloma cell, non-Hodgkin's lymphoma cell, chronic myelogenous leukemia cell, chronic lymphocytic leukemia cell, or acute myelogenous leukemia cell. The method may further comprise isolating the tissue sample from the subject.

The disclosure also features kits comprising any of the antibodies and anti-CD38-attenuated interferon alpha-2b fusion constructs described and exemplified herein. The kits may be used to supply antibodies and other agents for use in diagnostic, basic research, or therapeutic methods, among others.

In some aspects, a kit comprises an anti-CD38-attenuated interferon alpha-2b fusion construct, the construct optionally comprised in a composition comprising a pharmaceutically acceptable carrier, and instructions for using the kit in one or more of a method for inhibiting or reducing proliferation of a tumor cell expressing CD38 on its surface, a method for inducing apoptosis in a tumor cell expressing CD38 on its surface, and/or a method for treating a tumor that comprises and/or is mediated by cells expressing CD38 on their surface. Such methods may be any method described or exemplified herein. The kits may comprise a pharmaceutically acceptable carrier. The kits may comprise one or more pharmaceutically acceptable auxiliaries and/or one or more pharmaceutically acceptable excipients. In the kits, the anti-CD38 antibody may be any antibody described or exemplified herein, and the attenuated interferon alpha-2b may comprise any attenuated interferon alpha-2b described or exemplified herein. The constructs may be comprised in sterile solutions ready for injection or intravenous administration, or may comprise a sterile, lyophilized form ready to be combined with a carrier just prior to use.

In some aspects, a kit comprises an anti-CD38 antibody and instructions for using the kit in a method for detecting CD38-positive cells in a sample, including a tissue sample isolated from a subject. The anti-CD38 antibody may be any antibody described or exemplified herein. The antibody may optionally be fused to an attenuated interferon alpha-2b protein.

The following examples are provided to describe the disclosure in greater detail. They are intended to illustrate, not to limit, the disclosure.

Example 1 Optimization of X355/02-HC-L0-IFN-alpha (A145D) IgG4

Other anti-CD38-attenuated IFN fusion proteins are described in PCT Application No. PCT/AU2012/001323. These include the antibody construct designated in the PCT application as X355/02-HC-L0-IFN-alpha (A145D) IgG4. In this specification, X355/02-HC-L0-IFN-alpha (A145D) IgG4 has been renamed as A02.1. The heavy chain sequence of the antibody comprises the amino acid sequence of SEQ ID NO: 11, and the light chain sequence comprises the amino acid sequence of SEQ ID NO: 12. The variable light chain of A02.1 (SEQ ID NO: 14) was co-expressed with its variable heavy chain A02.1 (SEQ ID NO: 13) formatted on a human IgG4 constant region containing the substitution S228P (EU Numbering) (SEQ ID NO: 3). This antibody is referred to herein as X02.1. A02.1 includes a fusion to IFN-alpha2b whilst X02.1 does not, despite both antibodies sharing identical heavy chain and light chains sequences.

A BLAST search (Altschul S F (1997) Nucleic Acids Res. 25:3389-3402) against a database of human germline immunoglobulin genes was performed using the amino acid sequence of the variable heavy chain of X02.1. The closest human germline variable heavy chain gene was IGHV4-61*01 (SEQ ID NO: 16). An alignment of the X02.1 VH and IGHV4-61*01 is shown in FIG. 2. The X02.1 variable heavy region differs by eight amino acids from its closest germline amino acid sequence. In order to reduce the immunogenicity of the X02.1 heavy chain variable region, germline amino acid residue substitutions could be produced at residues where it differs from the germline sequence and the resulting antibody variants tested for anti-CD38 binding activity.

Several heavy chain variants of the X02.1 parental sequence are detailed in FIG. 2. These heavy chain variable regions were formatted onto the IgG4 S228P constant region, and co-expressed with the A02.1 light chain. Tables 1a and 1b detail the sequences of the variants tested along with their ability to bind human CD38 as assessed using flow cytometry and surface plasmon resonance (SPR). Briefly, antibody chains were transiently co-expressed in CHO cells and purified via Protein A chromatography as described in the Example 5. Flow binding assays as described in Example 5 were used to assess the variants. The EC₅₀ of the dose response curve obtained for each antibody is also given in Tables 1a and 1b.

TABLE 1a Variable Heavy ARP-1 Chain flow Amino Acid Variable Variable binding Substitution Heavy Light CD38 assay Antibody (Relative to SEQ ID SEQ ID binding (EC₅₀ in Designation X02.1) NO: NO: by SPR μg/mL) X02.8 L74S 17 14 2.30 × 10⁻⁸ 18.3 X02.9 H40P 18 14 2.63 × 10⁻⁸ N/T X02.10 T(82A)S 19 14 2.07 × 10⁻⁸ N/T X02.11 L74S, I78F 20 14 2.39 × 10⁻⁸ 18.1 R81K, T(82A)S X02.108 I78F 32 14 2.63 × 10⁻⁸ N/T X02.110 R81K 33 14 2.07 × 10⁻⁸ N/T N/T—Protein was not able to be purified and was not tested.

TABLE 1b Variable Heavy ARP-1 Chain flow Amino Acid Variable Variable binding Substitution Heavy Light CD38 assay Antibody (Relative to SEQ ID SEQ ID binding (EC₅₀ in Designation X02.1) NO: NO: by SPR μg/mL) X02.69 Q2V 22 14 3.68 × 10⁻¹¹ 16.8 X02.71 I29V 24 14 1.29 × 10⁻¹⁰ 3.5 X02.78 S32G 31 14 2.04 × 10⁻¹¹ N/T N/T—Protein not purified or tested.

SPR binding of the variants detailed in Table 1a was evaluated separately to those of Table 1b. The K_(D) (M) of the parental antibody X02.1 ranged from 2.7×10⁻⁸ to 3.78×10⁻¹⁰ in the SPR binding experiments. Flow cytometry binding experiments showed antibodies X02.8, X02.11, X02.69 and X02.71 bound strongly to the CD38 positive cell line ARP-1.

Antibodies with the above amino acid substitutions were subsequently explored in the context of a fusion protein through conjugation to attenuated IFN-alpha2b (termed A02 when linked to IFN, with the number following the decimal representing the same variant having the X02 designation). These heavy chain variable regions were formatted onto an IgG4 constant region comprising the substitution S228P fused to A145D attenuated IFN-alpha2b and co-expressed in CHO or HEK cells with the A02.1 light chain as described in the Example 5. Proteins that were successfully purified from cell supernatant were then tested in a flow binding assay to the cell line ARP-1. The EC₅₀ value of the dose response curve for each antibody is given in Table 2. All antibody-attenuated IFN fusion constructs tested bound to the CD38 positive cell line ARP-1. It was observed that heavy chain variant X02.9 (not fused to IFN) could not easily be purified whereas an identical variant fused to IFN (A02.9) was purified. In some cases, attenuated IFN fusion proteins could be expressed and purified, when the equivalent monoclonal antibody appeared more difficult to be expressed and/or purify.

TABLE 2 Variable Heavy Chain CD38 ARP-1 flow Anti-CD38- Amino Acid Variable Variable Protein binding binding attenuated Substitution Heavy Light Acapture by by SPR assay IFN fusion (Relative to SEQ ID SEQ ID SPR (RU) at (EC₅₀ in protein A02.1) NO: NO: (RU)* 350 sec* μg/mL) A02.8 L74S 17 14 4697 833 1.9 A02.9 H40P 18 14 4718 841 1.0 A02.10 T(82A)S 19 14 4647 804 1.5 A02.11 L74S, I78F, 20 14 4483 827 3.5 R81K, T(82A)S *Note: The amount of Anti-CD38 attenuated IFN fusion protein in the cell culture supernatant is indicated by the Protein A capture by SPR. The CD38 binding by SPR refers to the amount of CD38 that remains bound to the surface after 350 seconds of the dissociation phase.

BLAST searches using the amino acid sequence of the A02.1 variable light chain were performed against the database of human germline immunoglobulin genes. The closest human germline variable light chain gene was IGLV5-37*01. An amino acid sequence alignment of A02.1VL and IGLV5-37*01 is given in FIG. 3. This alignment illustrates a 12 amino acid difference between these sequences.

Several amino acid substitutions were made in the X02.1 variable light chain. These substitutions are shown in FIG. 3. Co-expression of these light chain variable regions with the X02.1 variable heavy chain formatted onto an IgG4 constant region containing the substitution S228P was performed in CHO cells as described in Example 5.

Antibodies purified from CHO cell supernatants were subsequently tested in flow cytometry-based binding assays to the CD38 positive cell line ARP-1. Table 3 details EC₅₀ values of the dose response curve obtained for each antibody.

TABLE 3 Variable ARP-1 Light Chain flow Amino Acid Variable Variable CD38 binding Substitution Heavy Light binding assay Protein A Antibody (Relative to SEQ ID SEQ ID by SPR (EC₅₀ in HPLC Designation A02.1) NO: NO: (KD) μg/mL) mg/L X02.95 A2P 13 53 4.40 × 10⁻¹² N/T 11.1 X02.96 A8P 13 54 2.50 × 10⁻¹⁰ 30.0 19.9 X02.97 L11S 13 55 7.51 × 10⁻¹² Low 15.0 Binding X02.98 R29S 13 56 5.84 × 10⁻¹² N/T 8.7 X02.99 Y30S 13 57 3.21 × 10⁻¹²  4.4 11.5 X02.100 H(54A)D 13 58 1.60 × 10⁻⁷  Low 18.9 Binding X02.101 V(66B)A 13 59 2.89 × 10⁻¹¹ 13.7 21.0 X02.102 T68A 13 60 1.20 × 10⁻¹⁰ 20.4 18.0 X02.103 S70T 13 61 1.28 × 10⁻⁹   9.4 27.9 X02.104 T90I 13 62  1.0 × 10⁻⁸  9.7 23.1 X02.105 S92P 13 63 3.31 × 10⁻⁸   12.7* 19.3 X02.106 G95A 13 64 4.47 × 10⁻⁸  N/T 11.6 N/T - Protein not purified or not tested. Low Binding - Minimal binding observed, not sufficient for an EC₅₀ value. *Antibody was tested in a flow binding assay against H929 cell line. Reported value is the EC₅₀ in μg/mL.

Antibodies X02.96, X02.99, X02.101, X02.102, X02.103 and X02.104 bound strongly to the CD38 positive ARP-1 cell line. X02.105 was able to bind strongly to the CD38 positive, H929 cell line.

Amino acid sequence analysis of the variable heavy chain sequence of X02.1 and A02.1 identified amino acids that could potentially undergo oxidation or isomerization. These include a potential isomerization site at D101 and a potential oxidation site at M(100C). To remove the potential isomerization and oxidation sites, amino acid substitutions were made as follows: D(101)E (SEQ ID NO: 30), M(100C)L (SEQ ID NO: 29) and the combination of both D(101)E and M(100C)L (SEQ ID NO: 27) (FIG. 2). Antibodies were made with combinations of these amino acid substitutions in the variable heavy chain as shown in Table 4. Antibody heavy chain variable regions were formatted with an IgG4 constant region containing the substitution S228P and co-expressed with the A02.1 light chain in CHO cells. Antibodies were then purified by Protein A chromatography and screened for binding to ARP-1 cells by flow cytometry. The binding data obtained is shown in Table 4.

TABLE 4 Variable ARP-1 Heavy Chain flow Amino Acid Variable Variable CD38 binding Substitution Heavy Light binding assay Protein A Antibody (Relative to SEQ ID SEQ ID by SPR (EC₅₀ in HPLC Designation X02.1) NO: NO: (KD) μg/mL) mg/L X02.76 M(100C)L 29 14 1.58 × 10⁻¹³ 4.1 24.8 X02.77 D101E 30 14 9.11 × 10⁻¹² 3.7 15.6 X02.74 M(100C)L, D101E 27 14 6.85 × 10⁻¹¹ N/T 21.8 N/T - Protein was not purified or not tested.

Antibodies X02.76 and X02.77 maintained their strong binding to the ARP-1 cell line indicating that the amino acids substitutions to remove the potential oxidation and isomerization sites in the X02.1 and A02.1 heavy chain had little impact on their CD38 binding activity. Combining these substitutions to form antibody X02.74 resulted in an antibody that did not purify using the protocol in Example 5.

Amino acid analysis of the variable light chain sequence of X02.1 and A02.1 identified amino acids that could potentially undergo oxidation or deamidation. These included a potential deamidation site at N69 and potential oxidation site at M89. Additionally a putative N-linked glycosylation site was predicted to exist within CDR3 of the light chain at position N94. The presence of N-linked glycans can cause heterogeneity in therapeutic proteins, complicating development. To remove these potential issues the following point variants were synthesized: N69A (SEQ ID NO: 39), M89L (SEQ ID NO: 52) and M891 (SEQ ID NO: 51), N94T (SEQ ID NO: 48), N94Q (SEQ ID NO: 38), G95P (SEQ ID NO: 50) and S96A (SEQ ID NO: 45) (see FIG. 3). Antibodies were generated by co-expression of the heavy- and light chains in CHO cells as detailed in Table 5. Antibodies were purified by Protein A chromatography and screened for binding to ARP-1 cells by flow cytometry. The binding data obtained is presented in Table 5.

TABLE 5 Variable ARP-1 Light Chain flow Amino Acid Variable Variable binding Substitution Heavy Light CD38 assay Protein A Antibody (Relative to SEQ ID SEQ ID binding (EC₅₀ in HPLC Designation A02.1) NO: NO: by SPR μg/mL) mg/L X02.81 N69A 13 39 2.67 × 10⁻¹⁰ N/T 12.6 X02.93 M89I 13 51 2.56 × 10⁻¹¹ 18.7 20.0 X02.94 M89L 13 52 3.48 × 10⁻¹² 8.7 18.9 X02.90 N94T 13 48 5.52 × 10⁻¹⁰ 26.2 23.0 X02.80 N94Q 13 38 1.44 × 10⁻⁹  13.2 30.3 X02.92 G95P 13 50 Low Binding Low 18.1 Binding X02.87 S96A 13 45 1.99 × 10⁻⁹  37.5 18.9 N/T - Protein was not purified or tested Low Binding - Minimal binding observed, not sufficient for an EC₅₀ or KD value.

X02.94 bound the CD38 positive cell line ARP-1 indicating that the substitution M89L had little impact on CD38 binding activity. The substitution N94Q in antibody X02.80 removed the potential N-linked glycosylation motif with minimal impact on CD38 binding activity as measure by flow cytometry (Table 5). Other substitutions that remove this glycosylation motif either resulted in antibodies that could not easily be purified or antibodies that exhibited attenuated binding to the CD38 positive cell line ARP-1. The potential deamidation site at position 69 was removed through substitution to alanine, though this antibody (X02.81) was not easily purified.

Other antibodies tested that comprised X02.1 variable heavy chain variants are listed in Table 6. These heavy chain variable regions were formatted on an IgG4 constant region containing an S228P substitution. These heavy chains were co-expressed with the A02.1 light chain in CHO cells. The antibodies were expressed and the resulting antibodies tested in flow cytometry-based assays for binding to the CD38-positive cell ARP-1. All variable heavy chain substitutions with the exception of T23K (SEQ ID NO:21; X02.68) had minimal impact on binding to the CD38 positive cell line ARP-1 in flow cytometry-based assays.

TABLE 6 Variable ARP-1 Heavy Chain flow Amino Acid Variable Variable binding Substitution Heavy Light CD38 assay Protein A Antibody (Relative to SEQ ID SEQ ID binding (EC₅₀ in HPLC Designation X02.1) NO: NO: by SPR μg/mL) mg/L X02.73 S19K 26 14 3.85 × 10⁻¹⁰ 4.3 20.6 X02.68 T23K 21 14 1.06 × 10⁻¹¹ N/T 17.0 X02.70 V71R 23 14 3.54 × 10⁻⁹  7.2 32.8 X02.75 T73K 28 14 6.38 × 10⁻¹⁰ 4.9 17.8 X02.72 T83R 25 14 1.63 × 10⁻⁹  3.6 30.6 N/T - Protein not purified or tested.

Antibodies comprising other light chain variable region substitutions in the X02.1 sequence were also produced. These variant light chains were combined with the X02.1 heavy chain formatted onto an IgG4 constant region containing the substitution S228P and expressed in CHO cells as described in Example 5. A summary of the heavy- and light chains used to produce these antibody variants is given in Table 7. Antibodies X02.83, X02.85, X02.91, X02.82 bound strongly to the CD38 positive cell line ARP-1.

TABLE 7 Variable Light Chain ARP-1 flow Amino Acid Variable Variable binding Substitution Heavy Light CD38 assay Protein A Antibody (Relative to SEQ ID SEQ ID binding (EC₅₀ in HPLC Designation A02.1) NO: NO: via SPR μg/mL) mg/L X02.83 E17A 13 41 2.69 × 10⁻⁹  8.2 32.8 X02.86 D(27A)G 13 44 4.28 × 10⁻⁹  120.4  30.0 X02.85 ΔD(L66A)*** 13 43 2.70 × 10⁻¹⁰ 6.3 17.6 ΔV(L66B)*** X02.107 E83I, D85T 13 65  2.47 × 10^(−8##) N/T 10.0* X02.91 P26R 13 49 7.07 × 10⁻¹⁰ 17.6  21.1 X02.88 N32R 13 46 Low binding Low Binding 33.5 X02.82 Y49R 13 40 N/T 3.8 27.9 X02.89 Y51R 13 47 Low binding No Binding 25.7 X02.84 Y49R, Y51R 13 42 Low binding No Binding 35.0 N/T - Protein was not purified or tested. Low Binding - Minimal binding observed, not sufficient for an EC50 value ***Δ indicates that this amino acid present in A02.1 light chain was removed from this sequence *estimated protein value based on protein A capture level by SPR ^(##)The SPR binding for X02.107 was evaluated in a separate experiment in which the KD of the parental antibody X02.1 was 2.7 × 10⁻⁸. The KD of the parental antibody X02.1 is 3.78 × 10⁻¹⁰ in the SPR binding experiment for all other antibodies tested.

Substitutions causing little impact on CD38 binding activity and the purification of X02 variant antibodies were subsequently produced as armed antibodies through fusion to A145D attenuated IFN-alpha2b. X02.1 light chain substitutions were combined and the resulting variants co-expressed with point- and combinatorial variants of the X02.1 heavy chain in HEK293E cells, as listed in Table 8. These antibodies were primarily focused on removing the potential X02.1 light chain deamidation site, an oxidation site from CDR3 of the X02.1 heavy chain and a putative strong MHC Class II binding peptide from framework region 3 of the X02.1 heavy chain predicted via in silico analyses (Epibase, Lonza, UK), FIG. 4.

TABLE 8 Variable Heavy Variable Light Anti-CD38- Chain Amino Chain Amino attenuated Acid Variable Acid Variable IFN Substitution Heavy Substitution Light fusion (Relative to SEQ (Relative to SEQ protein A02.1) ID NO: A02.1) ID NO: A02.2 None 13 E83I, D85T 65 A02.3 L74S 17 E83I, D85T 65 A02.4 H40P 18 E83I, D85T 65 A02.5 T(82A)S 19 E83I, D85T 65 A02.6 L74S, I78F, 20 E83I, D85T 65 R81K, T(82A)S A02.12 L74S, I78F, 34 E83I, D85T 65 R81K, T(82A)S, M(100C)L A02.13 H40P, L74S, 35 E83I, D85T 65 I78F, R81K, T(82A)S A02.37 L74S, I78F, 34 E83I, D85T, 66 R81K, T(82A)S, M89L M(100C)L A02.46 L74S, I78F, 34 E83I, D85T, 67 R81K, T(82A)S, N69Q M(100C)L A02.47 L74S, I78F, 34 E83I, D85T, 68 R81K, T(82A)S, N69T M(100C)L A02.48 L74S, I78F, 34 E83I, D85T, 69 R81K, T(82A)S, N69G M(100C)L A02.49 L74S, I78F, 34 E83I, D85T, 70 R81K, T(82A)S, N69H M(100C)L A02.50 L74S, I78F, 34 E83I, D85T, 71 R81K, T(82A)S, N69K M(100C)L A02.51 L74S, I78F, 34 E83I, D85T, 72 R81K, T(82A)S, N69P M(100C)L

The antibodies listed in Table 8 were analyzed for protein expression and binding to CD38 via surface plasmon resonance (SPR). Potency assays were also performed using cell culture supernatant taken from transfected cells to assess the relative activity of each of these anti-CD38-attenuated IFN fusion proteins as outlined in Example 5. The data obtained is given in Table 9.

TABLE 9 CD38 Annexin V Caspase binding Assay Assay Anti- by (Fold (Fold CD38- SPR change change Cell attenuated Protein A (RU) relative to relative to Proliferation IFN fusion HPLC at untreated untreated Assay protein (mg/L) 350 sec* cells) cells) IC₅₀ (μM) A02.2 30.2 756 N/T N/T N/T A02.3 21.6 835 N/T N/T N/T A02.4 27.3 809 N/T N/T N/T A02.5 22.0 788 N/T N/T N/T A02.6 33.7 895 N/T N/T N/T A02.12 25.3 N/A 2.7 7.0 236 A02.46 3.1 914 2.2 5.8 1190 A02.47 26.5 1455 3.10 4.44 N/T A02.48 3.4 921 2.0 5.6 562 A02.49 3.0 946 2.1 5.5 875 A02.50 3.1 809 1.9 6.1 1681 A02.51 1.8 368 2.0 5.8 3741 Note: The CD38 binding by SPR refers to the amount of CD38 that remains bound to the surface after 350 seconds of the dissociation phase. Annexin V Assay refers to cells positively stained by Annexin V-FITC after 24 h treatment with antibody constructs at 20 nM. Caspase Assay refers to caspase activation of cells after 24 h treatment with antibody constructs at 20 nM. N/A—Not Available; N/T—Not Tested

Of the proteins tested A02.12 expressed well and demonstrated potency in the Annexin V, Caspase and cell proliferation assays. Substitution of N69T in antibody A02.47 did not affect expression levels or potency in Annexin V or Caspase Assays suggesting that removal of this deamidation site is possible. Substitution N69T could be incorporated into other constructs herein to remove this putative deamidation site with minimal losses in the functional activity of the resulting antibody.

Example 2 In Silico Immunogenicity Analysis of the A02.1 Light Chain Amino Acid Sequence

Putative immunogenic epitopes were identified in the light chain variable region amino acid sequence of A02.1 using the Epibase analysis software (Lonza, UK). To remove putative immunogenic epitopes, substitutions were introduced into the A02.1 variable light chain (FIG. 4). Light chains with lower predicted immunogenicity were co-expressed in HEK293E cells with the A02.12 heavy chain variable region (SEQ ID NO: 34) formatted onto an IgG4 constant region containing the substitution S228P fused to A145D-attenuated IFN. The antibody variants produced are detailed in Table 10.

TABLE 10 Variable Variable Anti- Heavy Light CD38- Chain Amino Chain Amino attenuated Acid Variable Acid Variable IFN Substitution Heavy Substitution Light fusion (Relative to SEQ (Relative to SEQ protein A02.1) ID NO: A02.1) ID NO: A02.18 L74S, I78F, 34 E83I, D85T, 73 R81K, T(82A)S, L47E M(100C)L A02.19 L74S, I78F, 34 E83I, D85T, 74 R81K, T(82A)S, L47G M(100C)L A02.20 L74S, I78F, 34 E83I, D85T, 75 R81K, T(82A)S, L47N M(100C)L A02.21 L74S, I78F, 34 E83I, D85T, 76 R81K, T(82A)S, L47P M(100C)L A02.22 L74S, I78F, 34 E83I, D85T, 77 R81K, T(82A)S, L47S M(100C)L A02.23 L74S, I78F, 34 E83I, D85T, 78 R81K, T(82A)S, L48E M(100C)L A02.24 L74S, I78F, 34 E83I, D85T, 79 R81K, T(82A)S, L48P M(100C)L A02.25 L74S, I78F, 34 E83I, D85T, 80 R81K, T(82A)S, Y49E M(100C)L A02.26 L74S, I78F, 34 E83I, D85T, 81 R81K, T(82A)S, Y49Q M(100C)L A02.27 L74S, I78F, 34 E83I, D85T, 82 R81K, T(82A)S, Y50P M(100C)L A02.28 L74S, I78F, 34 E83I, D85T, 83 R81K, T(82A)S, Y50N M(100C)L A02.29 L74S, I78F, 34 E83I, D85T, 84 R81K, T(82A)S, Y50T M(100C)L A02.30 L74S, I78F, 34 E83I, D85T, 85 R81K, T(82A)S, Y51D M(100C)L A02.31 L74S, I78F, 34 E83I, D85T, 86 R81K, T(82A)S, S52E M(100C)L A02.32 L74S, I78F, 34 E83I, D85T, 87 R81K, T(82A)S, S52H M(100C)L A02.33 L74S, I78F, 34 E83I, D85T, 88 R81K, T(82A)S, S52Q M(100C)L A02.34 L74S, I78F, 34 E83I, D85T, 89 R81K, T(82A)S, H(54A)N M(100C)L A02.35 L74S, I78F, 34 E83I, D85T, 90 R81K, T(82A)S, H(54A)P M(100C)L A02.36 L74S, I78F, 34 E83I, D85T, 91 R81K, T(82A)S, K(54B)D M(100C)L

The above antibodies were analyzed for protein expression, binding to CD38 via SPR, and potency using the cell culture supernatant screen as described in Example 5. The results of these assays are detailed in Table 11. These data indicate that substitution of some residues to lower the predicted immunogenicity of the antibody results in Anti-CD38-attenuated IFN fusion proteins that express and have functional potency in the Annexin V, Caspase and Cell Proliferation Assays.

TABLE 11 Annexin Caspase CD38 V Assay Assay binding (Fold (Fold Anti-CD38- Protein by SPR change change Cell attenuated A (RU) at relative to relative to Proliferation IFN fusion HPLC 350 untreated untreated Assay protein (mg/L) sec* cells) cells) IC₅₀ (pm) A02.18 9.3 745 N/T N/T N/T A02.19 8.0 741 N/T N/T N/T A02.20 9.1 N/T 2.2 5.6 37 A02.21 3.3 DNB N/T N/T N/T A02.22 10.4 738 N/T N/T N/T A02.23 15.9 192 2.7 6.9 N/T A02.24 23.5 87 1.4 2.3 N/T A02.25 25.7 80 3.0 4.3 2477 A02.26 35.0 383 3.2 6.0 66 A02.27 12.3 DNB 1.3 2.5 29910 A02.28 16.1 422 2.7 6.3 N/T A02.29 19.7 150 2.7 5.8 133 A02.30 25.2 122 1.9 2.5 N/T A02.31 28.4 359 3.0 7.1 514 A02.32 13.5 663 2.7 7.7 60 A02.33 11.2 107 N/T N/T N/T A02.34 16.6 407 4.8 5.1 503 A02.35 11.2 738 2.4 4.8 3050 A02.36 16.7 192 2.8 8.0 N/T Note: The CD38 binding by SPR refers to the amount of CD38 that remains bound to the surface after 350 seconds of the dissociation phase. Annexin V Assay refers to cells positively stained by Annexin V-FITC after 24 h treatment with antibody constructs at 20 nM. Caspase Assay refers to caspase activation of cells after 24 h treatment with antibody constructs at 20 nM. DNB—Did not bind; N/T—Not Tested

Example 3 Multiple Amino Acid Substitutions Yield Optimized A02.1 Variants

By combining substitutions that improve the immunogenicity, manufacturability or potency of the anti-CD38 antibodies described above into a single gene construct, highly optimized anti-CD38 antibodies and anti-CD38-attenuated IFN fusion proteins were obtained. Table 12 summarizes such combinatorial substitutions and details heavy- and light chain combinations co-expressed in HEK293E cells and subsequently tested.

TABLE 12 Anti- Variable Heavy Variable Light CD38- Chain Amino Chain Amino attenuated Acid Variable Acid Variable IFN Substitution Heavy Substitution Light fusion (Relative to SEQ ID (Relative to SEQ ID protein A02.1) NO: A02.1) NO: A02.16 L74S, I78F, 34 R29G, Y30S 92 R81K, T(82A)S, E83I, D85T, M(100C)L M89L, N94Q A02.17 L74S, I78F, 34 R29G, Y30S 93 R81K, T(82A)S, E83I, D85T, M(100C)L M89L, N94E A02.52 L74S, I78F, 34 R29G, Y30S, 94 R81K, T(82A)S, S52Q, E83I, M(100C)L D85T, M89L, N94E A02.53 L74S, I78F, 34 Y30S, S52Q, 95 R81K, T(82A)S, E83I, D85T, M(100C)L M89L, N94E A02.54 L74S, I78F, 34 R29G, Y30S, 96 R81K, T(82A)S, S52Q, E83I, M(100C)L D85T, M89L, N94Q A02.55 L74S, I78F, 34 Y30S, S52Q, 97 R81K, T(82A)S, E83I, D85T, M(100C)L M89L, N94Q A02.56 L74S, I78F, 34 R29G, Y30S, 98 R81K, T(82A)S, S52E, M89L, M(100C)L E83I, D85T, N94E A02.57 L74S, I78F, 34 Y30S, S52E, 99 R81K, T(82A)S, E83I, D85T, M(100C)L M89L, N94E A02.58 L74S, I78F, 34 R29G, Y30S, 100 R81K, T(82A)S, S52E, E83I, M(100C)L D85T, M89L, N94Q A02.59 L74S, I78F, 34 Y30S, S52E, 101 R81K, T(82A)S, E83I, D85T, M(100C)L M89L, N94Q A02.60 L74S, I78F, 34 R29G, Y30S, 102 R81K, T(82A)S, S52Q, N69Q, M(100C)L E83I, D85T, M89L, N94E A02.61 L74S, I78F, 34 Y30S, S52Q, 103 R81K, T(82A)S, N69Q, E83I, M(100C)L D85T, M89L, N94E A02.62 L74S, I78F, 34 R29G, Y30S, 104 R81K, T(82A)S, S52Q, N69Q, M(100C)L E83I, D85T, M89L, N94Q A02.63 L74S, I78F, 34 Y30S, S52Q, 105 R81K, T(82A)S, N69Q, E83I, M(100C)L D85T, M89L, N94Q A02.64 L74S, I78F, 34 R29G, Y30S, 106 R81K, T(82A)S, S52E, N69Q, M(100C)L E83I, D85T, M89L, N94E A02.65 L74S, I78F, 34 Y30S, S52E, 107 R81K, T(82A)S, N69Q, E83I, M(100C)L D85T, M89L, N94E A02.66 L74S, I78F, 34 R29G, Y30S, 108 R81K, T(82A)S, S52E, N69Q, M(100C)L E83I, D85T, M89L, N94Q A02.67 L74S, I78F, 34 Y30S, S52E, 109 R81K, T(82A)S, N69Q, E83I, M(100C)L D85T, M89L, N94Q

Each antibody described in Table 12 was analyzed for protein expression, binding to CD38 via SPR, and potency using cell culture supernatant. The resulting data is given in Table 13. These results demonstrate that combining substitutions predicted to be beneficial in silico gave rise to some Anti-CD38-attenuated IFN fusion proteins that expressed and had functional potency in the Annexin V, Caspase and Cell Proliferation Assays.

TABLE 13 CD38 Annexin binding V Assay Caspase Cell Anti- by (Fold Assay (Fold Pro- CD38- Protein SPR change change liferation attenuated A (RU) at relative to relative to Assay IFN fusion HPLC 350 untreated untreated IC₅₀ protein (mg/L) sec* cells) cells) (pm) A02.14 8.1 1247 2.18 5.47 398 A02.15 29.6 1409 3.92 5.62 491 A02.16 5.7 1050 2.4 7.9 636 A02.17 10.0 1103 3.7 5.7 467 A02.52 2.8 416 2.0 5.4 2665 A02.53 3.0 545 2.2 4.7 6338 A02.54 1.8 250 1.9 5.9 15350 A02.55 2.1 436 2.2 4.5 12740 A02.56 2.0 178 1.7 4.3 13860 A02.57 2.7 345 2.5 6.6 6363 A02.58 2.3 273 1.9 4.9 9142 A02.59 1.2 388 2.0 4.7 6176 A02.60 1.3 DNB 1.5 3.3 185600 A02.61 1.2 DNB 1.7 4.1 65160 A02.62 1.3 DNB 1.8 5.0 55590 A02.63 1.2 DNB 1.7 3.4 152100 A02.64 1.1 DNB 1.8 3.2 89120 A02.65 1.4 DNB 1.6 4.1 37240 A02.66 1.3 DNB 1.6 4.0 57540 A02.67 1.6 DNB 2.3 3.9 82760 Note: The CD38 binding by SPR refers to the amount of CD38 that remains bound to the surface after 350 seconds of the dissociation phase. Annexin V Assay refer to cells positively stained by Annexin V-FITC after 24 h treatment with antibody constructs at 20 nM. Caspase Assay refers to caspase activation of cells after 24 h treatment with antibody constructs at 20 nM DNB—Did not bind; N/T—Not Tested

Example 4 Pairing of Different Heavy and Light Chain Anti-CD38 Antibodies

In order to determine if functional anti-CD38-attenuated IFN fusion proteins could be obtained, the heavy (SEQ ID NO: 110) and light (SEQ ID NO: 112) chains from the antibody X910/12-HC-L0-IFN-alpha (A145D) IgG4 described in PCT/AU2012/001323, and the heavy (SEQ ID NO: 111) and light (SEQ ID NO: 113) chains from the antibody X913/15-HC-L0-IFN-alpha (A145D) IgG4 described in PCT/AU12/001323, were paired with each other in various combinations and with heavy and lights chains described in the foregoing examples. A summary of the heavy and light chain pairings is provided listed in Table 14.

TABLE 14 Anti-CD38-attenuated Variable Heavy Variable Light IFN fusion protein SEQ ID NO: SEQ ID NO: A02.38 34 113 A02.39 34 112 A02.40 111 65 A02.41 110 65 X913/15-HC-L0-IFN- 111 113 alpha (A145D) IgG4 A02.43 110 113 A02.44 111 112 X910/12-HC-L0-IFN- 110 112 alpha (A145D) IgG4

Each antibody produced was analyzed for protein expression, binding to CD38 via SPR, and potency using the cell culture supernatant potency assays. The results of these assays are presented in Table 15a. These data show that pairing different heavy and light chains from distinct antibodies gave rise to some Anti-CD38-attenuated IFN fusion proteins that expressed and had functional potency in the Annexin V, Caspase and Cell Proliferation Assays.

TABLE 15a Annexin V Caspase Assay (Fold Assay (Fold Anti-CD38- CD38 change change attenuated Protein A binding by relative to relative to IFN fusion HPLC SPR (RU) untreated untreated protein (mg/L) at 350 sec* cells) cells) A02.38 2.9 DNB 0.9 4.3 A02.39 21.3 66 2.5 6.6 A02.40 2.1 DNB 1.0 4.4 A02.41 50.0 165 2.6 6.7 X913/15-HC- 8.2 96 2.2 5.4 L0-IFN-alpha (A145D) IgG4 A02.43 2.5 DNB 0.9 4.1 A02.44 2.2 DNB 1.0 4.5 X910/12-HC- 27.1 125 2.6 5.9 L0-IFN-alpha (A145D) IgG4 Note: The CD38 binding by SPR refers to the amount of CD38 that remains bound to the surface after 350 seconds of the dissociation phase. Annexin V Assay refer to cells positively stained by Annexin V-FITC after 24 h treatment with antibody constructs at 20 nM. Caspase Assay refers to caspase activation of cells after 24 h treatment with antibody constructs at 20 nM. DNB—Did not bind.

A selection of the above Anti-CD38-attenuated IFN fusion proteins were purified and analyzed for binding to CD38 positive cells in cell based assays. In addition potency assays were repeated to give a more accurate determination of the relative activity of each Anti-CD38-attenuated IFN fusion protein. The results of these assays are given in Table 15b.

TABLE 15b Annexin Caspase V Assay Assay Cell Anti- ARP-1 (Fold (Fold Pro- CD38- Flow change change liferation attenuated binding relative to relative to Assay IFN fusion (EC₅₀, in untreated untreated IC50 protein μg/mL) cells) cells) (pM) Figures A02.1 1.45 1.86 4.2 278.2 13, 14, 15, 16, 17, 18, 19 A02.2 2.46 1.94 4.4 175.7 13, 19 A02.3 0.96 1.86 3.5 254.9 13, 19 A02.4 1.50 1.88 3.8 198.3 13, 19 A02.5 1.45 1.88 4.3 146.3 13, 19 A02.6 1.42 2.03 3.5 102.3 13, 15, 19, 20 A02.8 1.93 1.91 3.8 125.5 13, 19 A02.9 1.03 1.96 3.6 107.1 13, 19 A02.10 1.48 1.95 3.8 125.6 13, 19 A02.11 3.48 1.98 3.9 374 13, 19 A02.12 3.40* 1.40 3.4 23.66 14, 16, 19, 21 A02.14 10.01* 1.82 2.5 398.20 19 A02.15 1.97* 3.09 6.8 491.70 19 A02.16 3.89* 2.66 5.2 636.80 14, 19 A02.17 9.32* 2.23 3.2 467.1 14, 19 A02.18 1.64 1.55 3.7 78.72 19 A02.19 1.07 1.63 3.5 230.3 19 A02.20 15.92* 1.61 2.9 36 19 A02.22 1.58 1.91 3.8 207 19 A02.25 0.37* 1.42 2.4 2477 19 A02.26 37.99* 1.56 2.0 66 19 A02.27 LB* 1.06 1.0 29910 14, 16, 19 A02.29 0.48* 1.55 3.0 133 19 A02.31 0.26* 1.78 2.1 514 14, 16, 19 A02.32 LB* 1.83 3.3 605 19 A02.33 1.54 1.96 3.7 741 16, 19 A02.34 0.89* 3.06 4.7 503 19 A02.35 3.44* 1.71 1.5 3050 19 A02.37 LB* 2.05 4.3 128 19 A02.39 LB* 1.92 4.3 3714 19 A02.41 0.78* 2.01 3.4 554 14, 19 A02.42 LB* 1.52 3.3 310 19 A02.45 0.71* 1.66 1.6 1697 19 A02.47 16.35* 1.53 4.69 144.3 19 The flow binding refers to the concentration of antibody required to achieve 50% of maximal mean fluorescence intensity. Annexin V Assay refer to cells positively stained by Annexin V-FITC after 24 h treatment with antibody constructs at 20 nM. Caspase Assay refers to caspase activation of cells after 24 h treatment with antibody constructs at 20 nM. LB—low binding, not sufficient for an EC₅₀ value. *Antibody was tested in a flow binding assay against H929 cell line. Reported value is the EC₅₀ in μg/mL.

FIG. 5 lists the consensus variable heavy chain and FIG. 6 lists the consensus variable light chain of A02.1 related constructs with functional activity. It could be further envisioned that combinations of substitutions could be made such as those described for Anti-CD38 antibodies X02.114, X02.115, X02.116, X02.117, X02.118, X02.119 (FIG. 6), X02.120, X02.121, X02.122, X02.123, X02.124, X02.125, X02.126 or X02.127 (FIG. 30). Further the above Anti-CD38 antibodies could also be constructed as Anti-CD38-attenuated IFN fusion proteins and tested for functional activity as described herein.

H929 Multiple Myeloma Xenograft Model

The in vivo potency of A02.1 has been tested previously in the NCI-H929 s.c. multiple myeloma model as described in Example 5. A02.1 was shown to have potent anti-tumor activity. The data is presented in PCT/AU2012/001323.

The H929 multiple myeloma xenograft model could be used to test the anti-tumor activity of any of the Anti-CD38-attenuated IFN fusion proteins described above.

Attenuated IFN is Required for Potent Apoptotic and Caspase Activation in Tumor Cell Lines

Using the Annexin V assay and the Caspase Assay it was demonstrated that the potent apoptotic activity and caspase activation is dependent on the Anti-CD38-attenuated IFN fusion proteins containing an attenuated IFN (Table 16a, FIG. 18). In the Annexin V Assay the attenuated IFN containing proteins (A02.1 and A02.6) had 2-fold greater activity than the proteins not containing attenuated IFN (X02.1 and X02.6).

TABLE 16a Annexin V Caspase Anti- Assay (Fold Assay (Fold CD38- change change attenuated relative to relative to IFN fusion untreated untreated protein cells) cells) A02.1 3.57 5.60 X02.1 1.50 2.34 A02.6 2.03 3.5 X02.6 1.04 0.40 Annexin V Assay refer to cells positively stained by Annexin V-FITC after 24 h treatment with antibody constructs at 20 nM. Caspase Assay refers to caspase activation of cells after 24 h treatment with antibody constructs at 20 nM.

Example 5 General Methods

Production of antibodies and antibody-fusion constructs in HEK-293E cells. DNA plasmids encoding protein constructs (antibodies and antibody-IFN-alpha2b related constructs) were prepared using HiSpeed Plasmid Maxi Kit (Qiagen, Valencia, Calif.) and then transfected into HEK293E cells (CNRC, Montreal, Canada), grown in F17 synthetic medium supplemented with 0.45% (w/v) D-(+)-Glucose (Sigma, Castle Hill, NSW), 25 μg/mL Geneticin (Invitrogen, Carlsbad, Calif.), and 1×GlutaMAX (Invitrogen, Carlsbad, Calif.) using a commercially available transfection reagent and OptiMEM medium (Invitrogen, Carlsbad, Calif.). After allowing for expression for 6 days in an incubator supplied with 5% CO₂ and 120 rpm shaking, the culture media was isolated and subjected to affinity purification using Protein A Mab Select SuRe™ agarose beads (GE Healthcare, Piscataway, N.J.). Purified protein constructs were buffer-exchanged into 0.2M arginine HCl, 25 mM citric acid, 71.5 mM sodium hydroxide at pH 6.0 using a PD Midi-Trap G-25 column (GE Healthcare, Piscataway, N.J.) or a HiPrep 26/10 Desalting column (HiTrap Desalting HiPrep 26/10 Desalting). Purified protein constructs were then concentrated using 50 kDaAmicon Ultra centrifugal filter devices (Millipore, Billerica, Mass.), followed by protein concentration determination by reading absorbance at 280 nm.

Production of Antibodies and Antibody-Fusion Constructs in CHO Cells.

DNA plasmids encoding protein constructs (antibodies and antibody-IFN-alpha2b related constructs) were prepared using HiSpeed Plasmid Maxi Kit (Qiagen, Valencia, Calif.) and then transfected into CHO cells (Lonza) grown in Freestyle™ CHO Expression Medium (Invitrogen, Carlsbad, Calif.) using a commercially available transfection reagent and OptiPro SFM™ medium (Invitrogen, Carlsbad, Calif.). After allowing for expression for 6 days in an incubator supplied with 10% CO₂ and 120 rpm shaking, the culture media was isolated and subjected to affinity purification using Protein A Mab Select SuReagarose beads (GE Healthcare, Piscataway, N.J.). Purified protein constructs were buffer-exchanged into 0.2M arginine.HCl, 25 mM citric acid, 71.5 mM sodium hydroxide at pH 6.0 using a PD Midi-Trap G-25 column (GE Healthcare, Piscataway, N.J.) or a HiPrep 26/10 Desalting column (HiTrap Desalting HiPrep 26/10 Desalting). Purified protein constructs were then concentrated using 50 kDaAmicon Ultra centrifugal filter devices (Millipore, Billerica, Mass.), followed by protein concentration determination by reading absorbance at 280 nm.

Anti-CD38-attenuated IFN fusion proteins binding to CD38 as measured by Surface Plasmon Resonance (SPR). The capacity of anti-CD38 antibodies and anti-CD38-attenuated IFN fusion proteins to bind to human CD38 were measured using unpurified transfected cell supernatant prepared 7:1 with Non Specific Binding Reducer (GE Healthcare, Piscataway, N.J.). Briefly, using a Biacore™ 3000 or a T200, Protein A was immobilized onto Flow Cell (FC) 1 (FC1) and FC2 (or alternatively FC3 and FC4) of a CM5 research grade sensor chip using amine coupling, giving approximately 1500 RU. FC2 (or FC4) was used as a reference throughout the experiments. The experiments were run at 37° C. in HBS-P+ buffer (0.01 M HEPES, 0.15 M NaCl, 0.005% v/v Surfactant P20, pH 7.4). At a flow rate of 20 μl/min, both flow cells were regenerated with 10 μL 50 mM sodium hydroxide before 40 μL supernatant containing the protein was passed over FC1 (or FC3) only. 30 μL of CD38 (10 g/mL in running buffer) or 30 μL running buffer was injected over FC1 and FC2 with a 5 minute dissociation time. Both surfaces were regenerated twice with sodium hydroxide. Results were generated using the BIAevaluation software provided with the machine. Microsoft Excel was used for calculations. BIAevaluation software automatically subtracted the reference sensorgram giving a trace of FC2-1 (or FC4-3) for each sample. A double reference was performed for each antibody tested by subtracting the sensorgram with a CD38 injection from the sensorgram with a blank running buffer injection. The Protein A capture refers to the response units measured from a sensorgram at a fixed timepoint of 412.5 s and this corresponds to the level of protein captured on the Protein A surface. CD38 binding is the response units measured at 507.5 s and is an indication of the level of bound CD38 to the protein captured sensor. CD38 dissociation is the response units measured at 865.5 s and is an indication of the level of CD38 bound to the protein captured surface after approximately 300 s of dissociation phase. BIAevalution was used to fit the sensorgram using a Langmuir 1:1 equation in order to generate an equilibrium association constant (KD)

Protein A HPLC.

Supernatants were analyzed by Protein A HPLC using a POROS A/20 2.1×30 mm Id column (Applied Biosystems) connected to an Agilent 1100 chromatography system. The column was equilibrated with PBS pH7.4, and protein was eluted with PBS adjusted to pH 2.2. A standard curve was generated using known amounts of a monoclonal antibody in PBS. The chromatograms, at the wavelengths of 215 nm or 280 nm, were integrated using the manufacturer's software and the area under the curve (AUC) reported and interpolated against the generated standard curve to estimate concentration.

Flow Cytometry Binding of Antibodies and Anti-CD38-Attenuated IFN Fusion Proteins to a Human CD38 Positive Cell Line, ARP-1 and H929.

The multiple myeloma cell line ARP-1 was a gift from Bart Barlogie MD, PhD, Director of the Myeloma Institute at the University of Arkansas Medical Center (Little Rock, Ak.). It is described in Hardin J. et al. (1994) Blood. 84:3063-70). The multiple myeloma cell line NCI-H929 (H929) was purchased from ATCC (CRL-9068, Gazdar, Blood 67: 1542-1549, 1986).

The ability of the antibodies or antibody-interferon constructs to bind the human CD38-positive myeloma cell lines ARP-1 or H929 in flow cytometry-based assays was tested. ARP-1 cells or H929 cells (5×10⁵, as judged by trypan blue exclusion) were incubated with each protein or with a human IgG4 monoclonal antibody with irrelevant specificity protein construct at various concentrations in 50 μL of FACS buffer (PBS plus 1% fetal calf serum, FCS, 0.2M HEPES, 0.5M EDTA) in 96 well plates for 60 minutes on ice in the dark. Cells were washed three times with FACS buffer before incubation for 30 minutes in 50 μL of FACS buffer containing goat anti-human IgG (Fc-specific, conjugated to fluorescein isothiocyanate, FITC; Sigma-Aldrich, St. Louis, Mo.). After washing three times with FACS buffer, cells were fixed with 50 μL of PBS containing 4% formaldehyde v/v and incubated at 4° C. in the dark for 16 hours. Incubated cells in suspension were diluted with an additional 150 μL of FACS buffer and analyzed for binding by flow cytometry on a FACS Canto II (BD Biosciences, San Diego, Calif.) using forward scatter, side scatter and fluorescence intensity in the FITC channel. The value reported is the mean fluorescence intensity (MFI).

Target Assays

Daudi cell proliferation assay: This assay was used to quantify the anti-proliferative activity of IFNs and antibody-IFN fusion protein constructs on cells that display CD38. Daudi cells express CD38 as a cell surface associated antigen. The viability of cells was measured using the reagent CellTiter-Glo®, Cat #G7570, from Promega (Madison, Wis.). This is a luminescence-based assay that determines the viability of cells in culture based on quantitation of ATP. The signal strength is proportional to the number of viable cells in a microtiter plate well. The details of the assay are as follows: Daudi cells (obtained from ATCC, Manassas, Va.) were cultured in a T75 flask (TPP, Trasadingen, Switzerland, cat #90076) to a preferred density of between 0.5×10⁵ and 0.8×10⁵ viable cells/mL in RPMI 1640 (Mediatech, Inc., Manassas, Va., cat #10-040-CV) with 10% Fetal Bovine Serum (FBS; Hyclone, Logan, Utah cat #SH30070.03). Cells were harvested by centrifuging at 400×g for five minutes, decanting the supernatant, and resuspending the cell pellet in RPMI 1640+10% FBS. Cells were then counted and the density was adjusted to 3.0×10⁵ cells/mL in RPMI 1640+10% FBS. Then, 50 μL of cell suspension was aliquoted into each well of a 96 well round bottom tissue culture plate (hereafter, “experimental plate”) (TPP, cat #92067). On a separate, sterile 96 well plate (hereafter, “dilution plate”; Costar, Corning, N.Y. cat #3879), test articles were serially diluted in duplicate in RPMI 1640+10% FBS. Then, 50 μL/well was transferred from the dilution plate to the experimental plate. The experimental plate was then incubated for four days at 37° C. with 5% CO₂. A mixture of the manufacturer-supplied assay buffer and assay substrate (hereafter, “CellTiter-Glo® reagent”, mixed according to the manufacturer's instructions) was added to the experimental plate at 100 μL/well. The plate was shaken for two minutes.

Then, 100 μL/well was transferred from the experimental plate to a 96 well flat bottom white opaque plate (hereafter, “assay plate”; BD Biosciences, Franklin 5 Lakes, N.J. cat #35 3296). The content of the assay plate was then allowed to stabilize in the dark for 15 minutes at room temperature. The plate was read on a Victor 3V Multilabel Counter (Perkin Elmer, Waltham, Mass., model #1420-041) on the luminometry channel and the luminescence was measured. Results are presented as “relative luminescence units” (RLU). Data was analyzed using Prism 5 (Graphpad, San Diego, Calif.) using non-linear regression and three parameter curve fit to determine the midpoint of the curve (EC50).

ARP-1 Cell proliferation assay. This assay was used to quantify the anti-proliferative activity of IFNs and antibody-IFN fusion protein constructs against CD38 antigen positive cells. ARP1 cells express CD38 as cell surface associated antigens. The viability of cells was measured using the reagent CellTiter-Glo®, Cat #G7570, from Promega (Madison, Wis.). This is a luminescence-based assay that determines the viability of cells in culture by quantitation of ATP. The signal strength is proportional to the number of viable cells in a microtiter plate well.

The details of the assay are as follows: ARP-1 cells were cultured in a T175 flask (Costar, Corning, N.Y. Lakes, N.J., cat #CLS431080) to a preferred density of between 2.0×10⁵ and 2.0×10⁶ viable cells/mL in RPMI 1640 (Life Technologies, Mulgrave, VIC, cat #11875-093) with 10% Fetal Bovine Serum (FBS; AusGeneX, Molendinar, QLD, Australia cat #FBS500S). Cells were harvested by centrifuging at 400×g for five minutes, decanting the supernatant, and resuspending the cell pellet in RPMI 1640+10% FBS. Cells were then counted and the density was adjusted to 2.0×10⁵ cells/mL in RPMI 1640+10% FBS. Then, 50 μL of the cell suspension was aliquoted into each well of a 96-well flat bottom white opaque plate (hereafter, “experimental plate”; Costar, Corning, N.Y. Lakes, N.J., cat #CLS3917). On a separate, sterile 96-well plate (hereafter, “dilution plate”; Costar, Corning, N.Y. cat #3799), test articles were serially diluted in duplicate in RPMI 1640+10% FBS. Subsequently, 50 μL/well was transferred from the dilution plate to the experimental plate. The experimental plate was then incubated for four days at 37° C. with 5% CO₂. Each experimental plate included the parental antibody IFN construct as the relative control.

A mixture of the manufacturer-supplied assay buffer and assay substrate (CellTiter-Glo® reagent, mixed according to the manufacturer's instructions) was added to the experimental plate at 100 μL/well. The plate was shaken for two minutes. The content of the assay plate was then allowed to stabilize in the dark for 15 minutes at room temperature. The plate was read on a FLUOstar Galaxy plate reader (BMG Labtech, Durham, N.C.) on the luminometry channel and the luminescence was measured. Data was analyzed using Prism 5 (Graphpad, San Diego, Calif.) using non-linear regression and three parameter curve fit to determine the midpoint of the curve (EC₅₀).

Annexin V assay. H929 cells were harvested by centrifuging at 400×g for five minutes, decanting the supernatant, and resuspending the cell pellet in RPMI 1640+10% FBS. Cells were then counted and the density was adjusted to 1.0×10⁶ cells/mL in RPMI 1640+10% FBS. Then, 50 μL of the cell suspension was aliquoted into each well of 96-well round bottom clear plates (hereafter, “experimental plate;” Costar, Corning, N.Y. cat #CL3799). On a separate, sterile 96-well plate (hereafter, “dilution plate”; Costar, Corning, N.Y. cat #CL3799), test articles were diluted to 40 nM in quaduplicate in RPMI 1640+10% FBS. Subsequently, 50 μL/well was transferred from the dilution plate to the experimental plate. The experimental plate was then incubated for 24 hours at 37° C. with 5% CO₂. The cells were then centrifuged at 400×g for 5 min, supernatant decanted and resuspended in 100 μL of HEPES buffer containing Annexin V-FITC (1/200) and 7-AAD (1/50). The cells were then incubated for 15 min at room temperature and subsequently analyzed for Annexin V and 7-AAD staining by flow cytometry on a FACS Canto II (BD Biosciences, San Diego, Calif.) using forward scatter, side scatter, FITC and PerCP-Cy5.5 channels. Annexin V positive cells refer to cells positively stained by Annexin V-FITC after 24 h treatment with antibody constructs at 20 nM and is expressed as fold change relative to untreated cells.

Caspase assay. Activated caspases 2, 3, 6, 7, 8, 9, 10 were measured with the reagent Homogeneous Caspases Assay, fluorimetric Cat #12236869001, from Roche (West Sussex, UK) after treatment with test antibodies. The details of the assay follow.

ARP-1 cells, which express high levels of CD38, were cultured in a T175 flask (Costar, Corning, N.Y., cat #CLS431080) to a preferred density of between 2.0×10⁵ and 2.0×10⁶ viable cells/mL in RPMI 1640 (Life Technologies, Mulgrave, VIC, cat #11875-093) with 10% FBS (AusGeneX, Molendinar, QLD, Australia cat #FBS500S). Cells were harvested by centrifuging at 400×g for five minutes, decanting the supernatant, and resuspending the cell pellet in RPMI 1640 Phenol red-free (Life Technologies, Mulgrave, VIC, cat #11835-030) +10% FBS. Cells were then counted and the density was adjusted to 2.0×10⁵ cells/mL in RPMI 1640 Phenol red free+10% FBS. Then, 50 μL of the cell suspension was aliquoted into each well of a 96-well flat bottom black-walled clear bottom plate (hereafter, “experimental plate”; Costar, Corning, N.Y. cat #CLS3603). On a separate, sterile 96-well plate (hereafter, “dilution plate”; Costar, Corning, N.Y. cat #3799), test articles were diluted to 40 nM in quadruplicate in RPMI 1640 Phenol red free+10% FBS. Subsequently, 50 μL/well was transferred from the dilution plate to the experimental plate. The experimental plate was then incubated for 24 hours at 37° C. with 5% CO₂. The manufacturer-supplied assay buffer was added to the manufacturer-supplied substrate and mixed according to the manufacturer's instructions to create the “substrate solution.” Then, 100 μL of the substrate solution was added to each well of the assay plate. The plate was shaken for 2 minutes. The plate was then incubated at room temperature for 15 minutes in the dark and finally read on FluoStar Galaxy plate reader (BMG Labtech, Durham, N.C.) with an excitation filter 470-500 nm and emission filter 500-560 nm and the fluorescence measured and presented as fold change relative to untreated cells. Caspase Assay refers to caspase activation of cells after 24 h treatment with antibody constructs at 20 nM.

Off-Target Assays

iLite gene reporter assay. The “off-target” iLite assay (PBL Interferon Source, Piscataway, N.J., Cat #51100) was performed largely as described by the manufacturer, with the addition of a human IgG blocking step. The iLite cell line is described by the manufacturer as “a stable transfected cell line derived from a commercially available pro-monocytic human cell line characterized by the expression of MHC Class II antigens, in particular the human lymphocyte antigen (HLADR), on the cell surface.” The cell line contains a stably transfected luciferase gene, the expression of which is driven by an interferon-response element (IRE), which allows for interferon activity to be quantified based on luminescence output. The manufacturer supplied iLite plate (hereafter, assay plate) and diluent were removed from the −80° C. freezer and allowed to equilibrate to room temperature. Then, 50 μL of the diluent was added per well to the assay plate. The vial of manufacturer-supplied reporter cells was removed from the −80° C. freezer and thawed in a 37° C. water bath. Then, 25 μL aliquots of cells were dispensed into each well of the assay plate. Next, 12.5 μL of 8 mg/mL human IgG that was diluted into RPMI 1640+10% FBS (Sigma Chemicals, St. Louis, Mo.; cat #14506) was added per well. The contents were mixed and incubated at 37° C. for 15 minutes. On a separate “dilution plate,” test articles were serially diluted in duplicate in RPMI 1640+10% FBS. Then, 12.5 μL of the test articles were transferred from the dilution plate to the assay plate. The assay plate was then incubated at 37° C. with 5% CO₂ for 17 hours. The manufacturer-supplied assay buffer and substrate were removed from the −80° C. freezer and allowed to equilibrate to room temperature for two hours. The manufacturer-supplied assay buffer was added to the manufacturer-supplied substrate vial and mixed well according to the manufacturer's instructions to create the “luminescence solution.” Then, 100 μL of the luminescence solution was added to each well of the assay plate. The plate was shaken for 2 minutes. The plate was then incubated at room temperature for 5 minutes in the dark and finally read on a Victor 3V Multilabel Counter on a luminometry channel and the luminescence measured and presented as RLU. The data was analyzed with Graphpad Prism 5 as described for the “on-target (Daudi) assay.” To test anti-CD38 antibody-IFN fusion protein constructs in the iLite assay, manufacturer-supplied diluent was supplemented with 0.25 mg/mL anti-CD38 antibody (same antibody clone being tested as an antibody-IFN fusion protein construct, to block any binding of the anti-CD38 antibody-IFN fusion protein constructs to the CD38 expressed on the iLite cells).

HEK-Blue Off-target assay. The assay was used to quantify the ability of antibody-IFN fusion constructs to bind interferon-alpha/β receptor (IFNAR) using the HEK-Blue™ IFN-alpha/β cell line (InvivoGen, San Diego, Calif.). The “off-target (HB-IFN) assay” was performed largely as described by the manufacturer of the HEK-Blue IFN-alpha/β cell line. HEK-Blue™ IFN-alpha/β Cells are specifically designed to monitor the activation of the JAK-STAT pathway, which is induced by type I IFNs. The cells were generated by introducing the human STAT2 and IRF9 genes into HEK293 cells to obtain a fully active type I IFN signalling pathway. The HEK-Blue™ IFN-alpha/β Cells stably express a reporter gene, secreted embryonic alkaline phosphatase (SEAP), under the control of the ISG54 promoter. ISG54 is a well-known ISG activated through an ISRE-dependent mechanism by type I IFNs. Upon IFN-alpha or IFNβ stimulation, HEK-Blue™ IFN-alpha/3 cells activate the JAK-STAT pathway and then the expression of the SEAP reporter gene. SEAP is secreted into the media and can be quantitated using the colorimetric reagent QUANTI-Blue™. Briefly, HEK-Blue IFN-alpha/β cells (Invivogen, San Diego Calif. cat #hkb-ifnab) were thawed and cultured in DMEM media (Mediatech, Manassas Va., cat #10-013-CV)+10% FBS (Hyclone, Logan Utah, cat #SH30070.03) that had been heat inactivated (HI FBS). When the cells reached 60-80% confluence, they were lifted with Cell Stripper (Mediatech, cat #25-056-CI). Cells were washed twice in DMEM+HI FBS and counted. Cells were adjusted to 3.3×10⁵ viable cells/mL in DMEM+HI FBS and 150 μL was aliquoted per well into a flat bottom 96 well tissue culture plate (hereafter, the “experimental plate”). Then, 50 μL of IFN-alpha2b or fusion protein construct, diluted into DMEM+HI FBS, was added per well. The plate was incubated at 37° C. 5% CO₂ for 16-24 hours. QUANTI-Blue (Invivogen, cat #rep-qb1) was prepared according to the manufacturer's directions. QUANTI-Blue (150 μL) was aliquoted into each well of a flat bottom plate (hereafter, the “assay plate”). Then, 50 μL supernatant per well from the experimental plate was transferred to assay plate. Assay plate was then incubated at 37° C. for 1-3 hours. Assay plate absorbance at 630 nm was read on a model 1420-41 Victor 3V Multilabel Counter from Perkin-Elmer. Data was analyzed using Graph Pad Prism.

H929 Xenograft Model

The effect of different doses of the A10.38 and A10.0 anti-CD38-attenuated IFN-alpha fusion protein constructs, were compared to the non-CD38-targeted fusion protein construct, on myeloma tumor growth. For these comparisons, the NCI-H929 s.c. multiple myeloma model was used.

The multiple myeloma cell line, NCI-H929 (ATCC CRL-9068, Gazdar, Blood 67: 1542-1549, 1986) is grown subcutaneously in immunocompromised (SCID) mice.

Eight to twelve week old CB.17 SCID mice were injected subcutaneously in the flank with 1×10⁷ NCI-H929 tumor cells in 50% Matrigel. When average tumor size reached 170-350 mm³, mice were grouped into 4 cohorts of 7 mice each and treatment began at time zero (TO). All treatments were given by intraperitoneal injection, (i.p.) twice weekly for 3 weeks (indicated by bar under graph). All compounds were dosed at 100 μg/dose (approximately 4.5 mg/kg) except vehicle group. Tumor volume was measured twice weekly by caliper measurement. Endpoint was tumor volume of 2,000 mm³.

The effect of different doses of the A02. 6, A10.0 and A10.38 anti-CD38-attenuated IFN-alpha fusion protein constructs, were compared to vehicle, on myeloma tumor growth. For these comparisons, the NCI-H929 s.c. multiple myeloma model was used.

The multiple myeloma cell line, NCI-H929 (ATCC CRL-9068, Gazdar, Blood 67: 1542-1549, 1986) is grown subcutaneously in immunocompromised (SCID) mice.

Eight to twelve week old CB.17 SCID mice were injected subcutaneously in the flank with 1×10⁷ NCI-H929 tumor cells in 50% Matrigel. When average tumor size reaches 90 mm³, mice will be grouped into 4 cohorts of 5 mice each and treatment begin at time zero (TO). All treatments will be given by intraperitoneal injection, (i.p.) twice weekly for 3 weeks (indicated by bar under graph). All compounds will be dosed at 100 μg/dose (approximately 4.5 mg/kg) except vehicle group. Tumor volume will be measured twice weekly by caliper measurement.

Example 6 Anti-CD38-Attenuated IFN Fusion Protein with Alternative Constant Region

A02.12 comprises an anti-CD38-attenuated IFN fusion protein in which the constant region of the protein is HC-L0-IFN-alpha (A145D) IgG4 (SEQ ID NO: 9). The heavy chain variable region of this antibody was reformatted onto an IgG1 constant region fused to A145D attenuated IFN-alpha2b (SEQ ID NO: 10). Co-expression of this heavy chain with the light chain of X02.107 (SEQ ID NO: 65) in HEK293E cells yielded antibody A02.112. Comparison of antibodies A02.12 and A02.112 using flow cytometry-based CD38-binding assays and potency assays demonstrates that other antibody constant regions, such as human IgG1, may also be used resulting in antibody-attenuated IFN fusion proteins with potent biologic activity equivalent to those generated using a human IgG4 constant region (Table 16b).

TABLE 16b Annexin Caspase V Assay Assay Cell Anti- Flow (Fold (Fold Pro- CD38- binding change change liferation attenuated (EC₅₀ relative to relative to Assay IFN fusion in μg/ untreated untreated IC₅₀ protein mL) cells) cells) (pm) Figures A02.12 3.40* 1.40 2.70 23.66 FIG. 21 A02.112 <0.3*   3.14 3.74 N/T FIG. 21 Note: *Antibody was tested in a flow binding assay against H929 cell line. Reported value is the EC₅₀ in μg/mL. Annexin V Assay refer to cells positively stained by Annexin V-FITC after 24 h treatment with antibody constructs at 20 nM. Caspase Assay refers to caspase activation of cells after 24 h treatment with antibody constructs at 20 nM. N/T—Not Tested

Example 7 Humanization of R5D1, R5E8 and R10A2 Variable Regions

Rat-derived anti-CD38 antibodies R5D1, R5E8 and R10A2 are described in PCT/AU12/001323 and were selected for humanization. The variable regions of these antibodies were superhumanized as described in U.S. Publ. No. 2003/0039649. Briefly, canonical structures were assigned to each rodent heavy and light chain through inspection of their respective amino acid sequences. R10A2 was assigned the canonical structure 2-1-1/1-2 (V_(L)/V_(H)), R5E8 was assigned the canonical structure 4-1-1/1-2, and R5D1 was assigned the canonical structure 2-1-1/1-2. Human germline sequences of the same canonical structure were used as acceptor frameworks for the grafting of donor CDRs. Variants of the resulting superhumanized antibody genes containing amino acid substitutions at positions within their sequences deemed likely to be important for maintenance of their binding activity were also designed. The different heavy chain superhumanized variable regions are shown in FIG. 7. The different light chain superhumanized variable regions are shown in FIG. 8.

Heavy chain variable region sequences were subcloned into vector pEE6.4 containing a human IgG4 constant region possessing the substitution S228P fused to A145D attenuated IFN-alpha2b (SEQ ID NO: 9). Light chain variable regions were subcloned into vector pEE12.4 containing a human kappa constant region (SEQ ID NO: 5). Antibodies were produced through co-expression of heavy chains in pEE6.4 and light chains in pEE12.4 in CHO cells as described previously. Table 17 summarises the heavy- and light chain pairings used to produce each superhumanized 5D1-based protein. Table 18 details the heavy- and light chain pairings for the superhumanized 5E8-based protein generated, whilst the heavy- and light chain pairings used to generate superhumanized 10A2-based proteins are given in Table 19. One-shot equilibrium dissociation constant (K_(D)) ranking of the superhumanized antibodies was performed by BIAcore™ analysis of the resulting CHO transfection supernatants. The method was used to determine if the antibodies expressed (Protein A capture) and had a level of binding activity to human CD38.

TABLE 17 Anti-CD38- Variable Variable Protein A attenuated IFN Heavy Light K_(D) capture fusion protein SEQ ID NO: SEQ ID NO: (M) (RU) A5D1.0 114 125 2.28 × 10⁻⁹ N/A (chimeric) A5D1.1 115 126 2.95 × 10⁻⁸ 175 A5D1.2 115 127 2.95 × 10⁻⁸ 289 A5D1.3 115 128 2.35 × 10⁻⁸ 248 A5D1.4 115 129 2.85 × 10⁻⁸ 427 A5D1.5 115 130 1.84 × 10⁻⁷ 269 A5D1.6 115 131 2.32 × 10⁻⁸ 338 A5D1.7 116 126 1.05 × 10⁻⁸ 132 A5D1.8 116 127 6.80 × 10⁻⁹ 263 A5D1.9 116 128 9.93 × 10⁻⁸ 128 A5D1.10 116 129 5.69 × 10⁻⁹ 358 A5D1.11 116 130 1.64 × 10⁻⁸ 250 A5D1.12 116 131 5.61 × 10⁻⁹ 345 A5D1.13 117 126 1.44 × 10⁻⁸ 213 A5D1.14 117 127 1.52 × 10⁻⁸ 344 A5D1.15 117 128 1.46 × 10⁻⁸ 167 A5D1.16 117 129 1.37 × 10⁻⁸ 524 A5D1.17 117 130 3.28 × 10⁻⁸ 410 A5D1.18 117 131 1.01 × 10⁻⁸ 396 A5D1.19 118 126 1.01 × 10⁻⁸ 245 A5D1.20 118 127 1.07 × 10⁻⁸ 282 A5D1.21 118 128 7.94 × 10⁻⁹ 351 A5D1.22 118 129 8.97 × 10⁻⁹ 566 A5D1.23 118 130 2.14 × 10⁻⁸ 336 A5D1.24 118 131 8.01 × 10⁻⁹ 319 A5D1.25 119 126 DNB 165 A5D1.26 119 127 DNB 286 A5D1.27 119 128 DNB 265 A5D1.28 119 129 DNB 493 A5D1.29 119 130 DNB 275 A5D1.30 119 131 DNB 263 A5D1.31 120 126 1.05 × 10⁻⁷ 206 A5D1.32 120 127 1.20 × 10⁻⁷ 318 A5D1.33 120 128 9.83 × 10⁻⁸ 176 A5D1.34 120 129 1.06 × 10⁻⁷ 497 A5D1.35 120 130 6.07 × 10⁻⁷ 211 A5D1.36 120 131 8.58 × 10⁻⁸ 331 A5D1.37 121 126 1.01 × 10⁻⁷ 184 A5D1.38 121 127 1.21 × 10⁻⁷ 315 A5D1.39 121 128 9.55 × 10⁻⁸ 191 A5D1.40 121 129 1.22 × 10⁻⁷ 460 A5D1.41 121 130 5.60 × 10⁻⁷ 409 A5D1.42 121 131 8.54 × 10⁻⁸ 301 A5D1.43 122 126 1.78 × 10⁻⁸ 150 A5D1.44 122 127 1.76 × 10⁻⁸ 226 A5D1.45 122 128 1.42 × 10⁻⁸ 177 A5D1.46 122 129 1.51 × 10⁻⁸ 401 A5D1.47 122 130 1.89 × 10⁻⁸ 364 A5D1.48 122 131 1.20 × 10⁻⁸ 273 A5D1.49 123 126 6.32 × 10⁻⁹ 141 A5D1.50 123 127 5.64 × 10⁻⁹ 212 A5D1.51 123 128 4.97 × 10⁻⁹ 188 A5D1.52 123 129 4.07 × 10⁻⁹ 493 A5D1.53 123 130 6.98 × 10⁻⁹ 561 A5D1.54 123 131 4.49 × 10⁻⁹ 253 A5D1.55 124 126 6.48 × 10⁻⁹ 203 A5D1.56 124 127 8.44 × 10⁻⁹ 144 A5D1.57 124 128 5.59 × 10⁻⁹ 233 A5D1.58 124 129 5.37 × 10⁻⁹ 376 A5D1.59 124 130 1.05 × 10⁻⁸ 313 A5D1.60 124 131 4.57 × 10⁻⁹ 429 DNB—did not bind. N/A—Not available

TABLE 18 Anti-CD38- Variable Variable Protein A attenuated IFN Heavy Light K_(D) capture fusion protein SEQ ID NO: SEQ ID NO: (M) (RU) A5E8.0 (chimeric) 132 143 5.50 × 10⁻⁹ N/A A5E8.1 133 144 2.31 × 10⁻⁷ 267 A5E8.2 133 145 2.37 × 10⁻⁷ 459 A5E8.3 133 146 3.59 × 10⁻⁷ 281 A5E8.4 133 147 DNB 420 A5E8.5 134 144 1.75 × 10⁻⁷ 172 A5E8.6 134 145 1.57 × 10⁻⁷ 611 A5E8.7 134 146 2.58 × 10⁻⁷ 201 A5E8.8 134 147 8.09 × 10⁻⁷ 308 A5E8.9 135 144 1.05 × 10⁻⁸ 153 A5E8.10 135 145 2.13 × 10⁻⁸ 503 A5E8.11 135 146 2.69 × 10⁻⁸ 372 A5E8.12 135 147 DNB 212 A5E8.13 136 144 3.98 × 10⁻⁸ 301 A5E8.14 136 145 1.26 × 10⁻⁷ 543 A5E8.15 136 146 1.39 × 10⁻⁷ 504 A5E8.16 136 147 DNB 284 A5E8.17 137 144 2.76 × 10⁻⁸ 397 A5E8.18 137 145 8.81 × 10⁻⁸ 430 A5E8.19 137 146 1.09 × 10⁻⁷ 220 A5E8.20 137 147 DNB 397 A5E8.21 138 144 DNB 277 A5E8.22 138 145 DNB 409 A5E8.23 138 146 DNB 339 A5E8.24 138 147 DNB 266 A5E8.25 139 144 DNB 283 A5E8.26 139 145 DNB 395 A5E8.27 139 146 DNB 277 A5E8.28 139 147 DNB 290 A5E8.29 140 144 3.91 × 10⁻⁸ 207 A5E8.30 140 145 5.00 × 10⁻⁸ 255 A5E8.31 140 146 6.61 × 10⁻⁸ 267 A5E8.32 140 147 DNB 42 A5E8.33 141 144 1.12 × 10⁻⁸ 134 A5E8.34 141 145 1.63 × 10⁻⁸ 301 A5E8.35 141 146 1.85 × 10⁻⁸ 177 A5E8.36 141 147 DNB 10 A5E8.37 142 144 8.19 × 10⁻⁸ 200 A5E8.38 142 145 1.55 × 10⁻⁸ 328 A5E8.39 142 146 1.74 × 10⁻⁸ 232 A5E8.40 142 147 DNB 126 DNB—did not bind. N/A—not available

TABLE 19 Anti-CD38- SEQ ID: SEQ ID: Protein A attenuated IFN Variable Variable K_(D) capture fusion protein Heavy Light (M) (RU) A10A2.0 148 157 5.98 × 10⁻¹⁰ N/A (chimeric) A10A2.1 149 158 DNB 728 A10A2.2 149 159 DNB 689 A10A2.3 149 160 DNB 850 A10A2.4 149 161 DNB 996 A10A2.5 149 162 DNB 761 A10A2.6 149 163 DNB 890 A10A2.7 149 164 DNB 725 A10A2.8 150 158 7.18 × 10⁻⁷ 718 A10A2.9 150 159 6.62 × 10⁻⁷ 627 A10A2.10 150 160 9.13 × 10⁻⁷ 850 A10A2.11 150 161 2.37 × 10⁻⁷ 956 A10A2.12 150 162 1.18 × 10⁻⁶ 864 A10A2.13 150 163 6.80 × 10⁻⁷ 765 A10A2.14 150 164 DNB 645 A10A2.15 151 158 1.15 × 10⁻⁷ 488 A10A2.16 151 159 8.11 × 10⁻⁸ 759 A10A2.17 151 160 1.84 × 10⁻⁷ 684 A10A2.18 151 161 3.39 × 10^(−8/) 907 A10A2.19 151 162 1.84 × 10⁻⁷ 831 A10A2.20 151 163 1.23 × 10⁻⁷ 560 A10A2.21 151 164 DNB 337 A10A2.22 152 158 2.70 × 10⁻⁹ 890 A10A2.23 152 159 2.17 × 10⁻⁹ 828 A10A2.24 152 160 3.04 × 10⁻⁹ 803 A10A2.25 152 161 1.51 × 10⁻⁹ 1054 A10A2.26 152 162 3.51 × 10⁻⁹ 741 A10A2.27 152 163 2.42 × 10⁻⁹ 603 A10A2.28 152 164 3.69 × 10⁻⁸ 384 A10A2.29 153 158 2.77 × 10⁻⁸ 93 A10A2.30 153 159 2.15 × 10⁻⁸ 86 A10A2.31 153 160 5.82 × 10⁻⁸ 33 A10A2.32 153 161 8.49 × 10⁻⁹ 169 A10A2.33 153 162 5.66 × 10⁻⁸ 62 A10A2.34 153 163 3.88 × 10⁻⁸ 56 A10A2.35 153 164 DNB DNE A10A2.36 154 158 8.38 × 10⁻⁹ 221 A10A2.37 154 159 1.39 × 10⁻⁹ 858 A10A2.38 154 160 1.08 × 10⁻⁸ 178 A10A2.39 154 161 3.80 × 10⁻⁹ 357 A10A2.40 154 162 1.34 × 10⁻⁸ 217 A10A2.41 154 163 8.73 × 10⁻⁹ 202 A10A2.42 154 164 2.09 × 10⁻⁷ 175 A10A2.43 154 158 2.45 × 10⁻⁷ 621 A10A2.44 155 159 6.23 × 10⁻⁹ 220 A10A2.45 155 160 2.84 × 10⁻⁷ 881 A10A2.46 155 161 1.39 × 10⁻⁷ 1000 A10A2.47 155 162 3.28 × 10⁻⁷ 9 A10A2.48 155 163 2.52 × 10⁻⁷ 565 A10A2.49 155 164 DNB 499 A10A2.50 156 158 1.61 × 10⁻⁹ 567 A10A2.51 156 159 2.00 × 10⁻⁷ 603 A10A2.52 156 160 1.69 × 10⁻⁹ 723 A10A2.53 156 161 1.20 × 10⁻⁹ 729 A10A2.54 156 162 1.92 × 10⁻⁹ 639 A10A2.55 156 163 1.47 × 10⁻⁹ 692 A10A2.56 156 164 1.97 × 10⁻⁷ 383 DNB—did not bind. DNE—did not express.

For each family of humanized antibodies—5D1, 5E8 and 10A2—several humanized heavy and light chain combinations failed to either express protein, or to bind to human CD38. A considerable number of antibodies across all 3 families of humanized antibodies expressed and bound to human CD38 with equilibrium dissociation constants in the nanomolar (nM) range. A10A2.53 and A10A2.25, which share a common light chain were chosen for further optimization. A10A2.53 was renamed A10.0 and A10A2.25 was renamed A10.38.

Example 8 Improved Variants of A10.0

The A10.0 antibody was optimized through alterations to the variable heavy and/or light chain sequences with the aim of yielding a positive effect on the biophysical and in silico immunogenicity of the antibody whilst causing minimal impact on the functional activity of the antibody.

In-Silico Immunogenicity Analysis of A10.0 Heavy- and Light Chains

In silico immunogenicity analyses of the A10.0 heavy- and light chain variable regions were made using the Epibase software package. Several amino acid substitutions were introduced into the heavy- and light chain variable regions of A10.0 to remove potential immunogenic epitopes. An amino acid sequence alignment of the heavy chain variable region variants produced aligned with the humanised heavy chain (SEQ ID NO: 156) is shown in FIG. 9. An amino acid sequence alignment of the light chain variable region variants aligned with the humanised light chain (SEQ ID NO: 161) is shown in FIG. 10. Details of the heavy- and light chains variants co-expressed in HEK293E cells to produce proteins are summarised in Table 20.

TABLE 20 VH Amino VK Anti- Acid Amino CD38- Sub- Variable Acid Variable attenuated stitution Heavy Sub- Light IFN (Relative SEQ stitution SEQ fusion to ID (Relative to ID protein A10.0) NO: A10.0) NO: A10.1 A40E 165 N/A 161 A10.2 A40G 166 N/A 161 A10.3 A40H 167 N/A 161 A10.4 A40Q 168 N/A 161 A10.5 A40S 169 N/A 161 A10.6 A40V 170 N/A 161 A10.7 N35E 171 N/A 161 A10.8 N35P 172 N/A 161 A10.9 N35Q 173 N/A 161 A10.10 N35S 174 N/A 161 A10.11 R94E 175 N/A 161 A10.12 R94G 176 N/A 161 A10.13 R94P 177 N/A 161 A10.14 R94T 178 N/A 161 A10.15 K96G 179 N/A 161 A10.16 K96T 180 N/A 161 A10.17 N/A 156 K24E 181 A10.18 N/A 156 K24G 182 A10.19 N/A 156 K24P 183 A10.20 N/A 156 K24Q 184 A10.21 N/A 156 R54D 185 A10.22 N/A 156 I48D 186 A10.23 N/A 156 Y49E 187 A10.24 N/A 156 M89A 188 A10.25 N/A 156 M89E 189 A10.26 N/A 156 M89H 190 A10.27 N/A 156 M89K 191 A10.28 N/A 156 M89P 192 A10.29 N/A 156 M89Q 193 A10.30 N/A 156 M89S 194 A10.31 N/A 156 M89V 195 A10.32 N/A 156 Q90D 196 Each antibody generated using the heavy- and light chain pairings outlined in Table 20 was assessed for protein expression level and binding to CD38 via SPR. Furthermore, potency assays were performed using cell culture supernatants to assess the relative functional activity of each of these anti-CD38 antibody-attenuated IFN fusion proteins, Table 21.

TABLE 21 Annexin V (Fold Caspase change Assay CD38 relative (Fold Cell Anti-CD38- binding by to change Pro- attenuated Protein A SPR (RU) untreated relative to liferation IFN fusion HPLC at 350 cells) untreated Assay protein (mg/L) sec* Assay cells) (IC₅₀ pM) A10.1 16.9 1824 1.66 3.41 4078 A10.2 16.7 1821 1.66 5.19 7622 A10.3 25.0 2166 1.63 5.46 2148 A10.4 23.7 2169 1.63 5.78 4108 A10.5 28.0 2240 1.64 5.80 3046 A10.6 31.0 2097 1.57 5.76 2283 A10.7 26.5 DNB 1.18 1.09 No IC₅₀ A10.8 2.4 DNB N/T N/T N/T A10.9 18.3 176 1.48 2.07 No IC₅₀ A10.10 32.2 1072 1.57 4.97 18870 A10.11 28.3 98 1.57 3.64 No IC₅₀ A10.12 30.7 DNB 1.22 1.99 No IC₅₀ A10.13 30.6 123 1.31 2.67 No IC₅₀ A10.14 30.5 247 1.19 5.11 68270 A10.15 41.8 1254 1.52 5.44 5169 A10.16 24.2 1210 1.70 4.57 5224 A10.17 18.2 1686 1.79 6.11 3054 A10.18 32.5 2457 1.89 6.16 2178 A10.19 1.6 DNB 1.73 2.39 No IC₅₀ A10.20 12.2 1355 4.65 7.72 564 A10.21 19.9 1837 1.84 5.56 5330 A10.22 5.5 480 N/T N/T N/T A10.23 20.6 255 1.71 3.85 59720 A10.24 34.6 1943 4.14 6.75 399 A10.25 28.3 1778 1.87 6.09 4910 A10.26 5.7 706 N/T N/T N/T A10.27 7.4 136 N/T N/T N/T A10.28 2.2 48 N/T N/T N/T A10.29 10.9 1443 N/T N/T No IC₅₀ A10.30 25.4 1865 1.98 6.21 1438 A10.31 5.8 469 N/T N/T N/T A10.32 34.5 615 3.80 6.97 3628 The CD38 binding by SPR refers to the amount of CD38 that remains bound to the surface after 350 seconds of the dissociation phase. Annexin V Assay refer to cells positively stained by Annexin V-FITC after 24 h treatment with antibody constructs at 20 nM. Caspase Assay refers to caspase activation of cells after 24 h treatment with antibody constructs at 20 nM. DNB—Did not bind; N/T—not tested; No IC₅₀-potency not sufficient for an IC₅₀ value.

Analyses of the amino acid sequences of the variable heavy- and light chain sequences of A10.0 identified several potential deamidation sites and one potential oxidation site. Variable heavy chain substitution N98Q was prepared to remove a deamidation site from CDR3 of the heavy chain, SEQ ID NO: 197. A further variant of the A10.0 variable light chain containing the CDR2 substitution N53Q (SEQ ID NO: 198) was generated to remove this putative deamidation site. M89 within CDR3 of the light chain was also altered through amino acid substitutions at this position with the combined aims of removing this potential oxidation site and reducing the predicted immunogenicity of this region of the light chain. These substitutions are outlined in Table 22, along with the heavy and light chain pairings co-expressed to produce each anti-CD38-attenuated IFN fusion protein.

TABLE 22 Amino Acid Anti-CD38- Substitution attenuated IFN (Relative to Variable Heavy Variable Light fusion protein A10.0) SEQ ID NO: SEQ ID NO: A10.35 Heavy Chain 197 161 N(98)Q A10.36 Light Chain 156 198 N(53)Q

Each antibody generated using the heavy- and light chain pairings outlined in Table 22 was assessed for protein expression level and binding to CD38 via SPR. Furthermore, potency assays were performed using cell culture supernatants to assess the relative functional activity of each of these anti-CD38 antibody-attenuated IFN fusion proteins, Table 23

TABLE 23 CD38 Annexin V Caspase binding assay (Fold Assay Anti-CD38- Protein by SPR change (Fold change Cell attenuated A (RU) relative to relative to Proliferation IFN fusion HPLC at 350 untreated untreated Assay protein (mg/L) sec* cells)Assay cells) IC₅₀ (pM) A10.35 34.5 1889 1.83 6.16 6241 A10.36 52.4 1895 3.95 5.90 534.9 The CD38 binding by SPR refers to the amount of CD38 that remains bound to the surface after 350 seconds of the dissociation phase. Annexin V Assay refer to cells positively stained by Annexin V-FITC after 24 h treatment with antibody constructs at 20 nM. Caspase Assay refers to caspase activation of cells after 24 h treatment with antibody constructs at 20 nM.

Example 9 Generating Improved Variants of A10.38

A10.0 and A10.38 share a common light chain. The optimized light chain sequences of A10.0 were paired with the heavy chain of the A10.38 antibody with the aim of yielding a positive effect on the antibody's biophysical and in silico immunogenicity properties whilst having a minimal impact on functional activity. A summary of the changes and the pairings of heavy and light chains are described in Table 24.

TABLE 24 Anti-CD38- VK Amino Acid attenuated SEQ ID: Substitution SEQ ID: IFN fusion Variable (Relative to Variable protein Heavy A10.38) Light A10.38 152 N/A 161 A10.39 152 K24E 181 A10.40 152 K24G 182 A10.41 152 K24P 183 A10.42 152 K24Q 184 A10.43 152 R54D 185 A10.44 152 I48D 186 A10.45 152 Y49E 187 A10.46 152 M89A 188 A10.47 152 M89E 189 A10.48 152 M89H 190 A10.49 152 M89K 191 A10.50 152 M89P 192 A10.51 152 M89Q 193 A10.52 152 M89S 194 A10.53 152 M89V 195 A10.54 152 Q90D 196 A10.57 152 N53Q 198

Each of the above antibodies was assessed for protein expression level and binding to CD38 via SPR. Potency assays were performed using cell culture supernatants to assess the relative functional activity of each of these anti-CD38 antibody-attenuated IFN fusion proteins, Table 25.

TABLE 25 Annexin V Caspase Assay (Fold Assay (Fold Anti-CD38- CD38 change change attenuated Protein A binding by relative to relative to IFN fusion HPLC SPR (RU) untreated untreated protein (mg/L) at 350 sec* cells) cells) A10.38 119.7 1540 3.22 5.17 A10.39 113.4 1444 3.39 4.79 A10.40 117.8 1562 3.28 5.12 A10.41 89.7 1459 3.27 5.12 A10.42 111.7 1443 3.32 5.60 A10.43 94.1 1426 3.21 6.15 A10.44 51.9 969 3.08 5.66 A10.45 111.7 333 2.76 5.01 A10.46 120.0 1547 3.24 4.80 A10.47 107.3 1337 3.45 4.25 A10.48 45.5 865 3.06 5.48 A10.49 55.8 213 3.46 7.63 A10.50 11.3 172 2.96 5.61 A10.51 51.6 1320 2.34 6.16 A10.52 70.0 1512 3.21 5.62 A10.53 40.0 536 3.46 4.68 A10.54 61.3 583 3.10 6.20 A10.57 67.1 1431 3.06 6.04 The CD38 binding by SPR refers to the amount of CD38 that remains bound to the surface after 350 seconds of the dissociation phase. Annexin V Assay refer to cells positively stained by Annexin V-FITC after 24 h treatment with antibody constructs at 20 nM. Caspase Assay refers to caspase activation of cells after 24 h treatment with antibody constructs at 20 nM. N/T—Not Tested Attenuated IFN is Required for Potent Apoptotic and Caspase Activation in Tumor Cell Lines

The relative potency of anti-CD38 antibodies A10.0 (attenuated IFN fusion) and X10.0 (no fusion) were compared using the Annexin V, Caspase and the Cell Proliferation Assays outlined in Example 5. The relative potency of A10.38 and X10.38 was also compared, Table 26.

TABLE 26 Annexin V Caspase Assay (Fold Assay (Fold Anti-CD38- change change Cell attenuated relative to relative to Proliferation IFN fusion untreated untreated Assay protein cells) cells) IC₅₀ (pM) Figures A10.0 2.10 4.23 2081 FIG. 18 X10.0 1.27 1.70 No IC50 FIG. 18 A10.38 3.22 5.17 1118 FIG. 25 X10.38 1.46 2.09 No IC50 FIG. 25 Annexin V Assay refer to cells positively stained by Annexin V-FITC after 24 h treatment with antibody constructs at 20 nM. Caspase Assay refers to caspase activation of cells after 24 h treatment with antibody constructs at 20 nM.

These data demonstrate the potent apoptotic activity exhibited by antibodies A10.0 and A10.38 relative to X10.0 and X10.38 respectively necessitates the presence of the attenuated IFN fusion. No anti-proliferative activity was observed with antibodies without an attenuated IFN.

A consensus sequence alignment of heavy chain variable regions from proteins with functional activity is shown in FIG. 11. A consensus sequence alignment of light chain variable regions from proteins with functional activity is shown in FIG. 12. It could be further envisioned that combinations of substitutions could be made such as those described for Anti-CD38 antibodies X10.60, X10.61, X10.62, X10.63, X10.64, X10.65, X10.66, X10.67, X10.68, X10.69, X10.70, X10.71, X10.72, X10.73, X10.74, X10.75, X10.76, X10.77, X10.78, X10.79, X10.80, X10.81, X10.82, X10.83, X10.84, X10.85, X10.86, X10.87, X10.88, X10.89, X10.90, X10.91, X10.92, X10.93, X10.94, X10.95, X10.96, X10.97, X10.98, X10.99, X10.100, X10.101, X10.102, X10.103, X10.104, X10.105, X10.106, X10.107, X10.108, X10.109, X10.110, X10.111, X10.112, X10.113, X10.114, X10.115, X10.116, X10.117, X10.118, X10.119, X10.120, X10.121, X10.122, X10.123, X10.124, X10.125, X10.126, X10.127, X10.128, X10.129, X10.130, X10.131, X10.132, X10.133, X10.134, X10.135, X10.136, X10.137, X10.138, X10.139, X10.140, X10.141, X10.142, X10.143, X10.144, X10.145, X10.146, X10.147 (FIG. 11, FIG. 12). Further the above Anti-CD38 antibodies could also be constructed as Anti-CD38-attenuated IFN fusion proteins and tested for functional activity as described herein.

H929 Multiple Myeloma Xenograft Model

The in vivo potency of 10A2 variants A10.0 and A10A2.0 were evaluated in an NCI-H929 s.c. mouse multiple myeloma model, FIG. 27. Both were shown to have potent anti-tumour activity in this model. Such a model could be used to test for anti-tumor activity of other protein constructs described within.

Off-Target Activity for the 10A2 Variants

The off-target activity of the 10A2 variants A10.0, A10.38, A10A2.37 and A10A2.39 in comparison with the parental A10A2.0 chimeric antibody fused to wildtype and attenuated interferon 145D was assessed in either the iLite reporter gene assay and/or the HEK Blue assay and is shown in FIG. 28 and FIG. 29. The EC₅₀ values are provided in FIG. 28 and FIG. 29. The off-target activity confirms the attenuation of the interferon and the need for the antibody to be targeted to CD38 to restore function.

Further In-Vitro Potency Data for A10.0 and Related Constructs

A selection of the above Anti-CD38-attenuated IFN fusion proteins were purified and analysed for binding to CD38 positive cells in cell based assays. In addition potency assays were repeated to more accurately determine the relative activity of each of these Anti-CD38-attenuated IFN fusion proteins. The methods for these various assays are described in Example 5. The results of each of these assays are given in Table 27.

TABLE 27 Annexin V Caspase Assay (Fold Assay (Fold Anti-CD38- H929 Flow change change Cell attenuated binding relative to relative to Proliferation IFN fusion (EC₅₀ in untreated untreated Assay IC₅₀ protein μg/mL) cells) cells) (pM) Figures A10.0 1.49 3.05 1.38 120.8 17, 18, 21, 22, 23, 24, 25, 26, 27 28, 29 A10.1 1.03 1.34 4.63 63.6 24, 25 A10.2 0.57 1.37 4.37 45.6 24, 25 A10.3 0.55 1.43 5.52 65.8 24, 25 A10.5 0.48 3.27 1.61 53.79 24, 25 A10.6 0.35 3.16 1.66 98.85 24, 25 A10.10 6.84 3.02 1.64 1967.00 24, 25 A10.14 2.26 2.46 1.56 2207 22, 24, 25 A10.15 2.06 3.06 2.55 174.4 22, 24, 25 A10.16 1.17 1.35 5.18 49.5 24, 25 A10.18 1.03 2.95 1.70 124.2 22, 24, 25 A10.20 2.11 2.84 1.26 656 24, 25 A10.21 0.78 3.0 1.39 147.3 22, 24, 25 A10.24 0.81 2.95 7.47 87.99 22, 24, 25 A10.25 1.37 2.75 1.38 27.69 24, 25 A10.30 0.88 3.22 1.60 18.73 24, 25 A10.32 51.69 1.93 1.19 381.4 24, 25 A10.35 1.10 2.97 2.05 93.96 22, 24, 25 A10.36 1.53 3.21 3.61 57.83 22, 24, 25 A10.37 18.57 2.53 1.40 163.5 24, 25 A10.38 1.13 3.27 1.53 36.79 23, 24, 25, 26, 29 A10.40 0.99 1.44 5.16 3.02 24, 25 A10.42 1.61 1.58 1.78 155.3 24, 25 A10.43 1.20 1.64 1.79 120.9 24, 25 A10.44 1.65 1.58 1.91 308.6 24, 25 A10.46 0.73 1.84 5.99 2.63 24, 25 A10.47 0.79 1.70 1.53 5.707 24, 25 A10.48 1.72 1.58 1.60 22.33 24, 25 A10.53 1.32 1.56 1.67 56.01 24, 25 A10.54 5.90 1.52 1.43 2008 24, 25 A10.56 2.43 1.84 1.95 141.7 24, 25 A10.57 1.54 1.49 4.71 126.1 24, 25 A10.59 0.89 2.48 2.38 45.75 21, 24, 25 The flow binding was determined in H929 cell line. Annexin V Assay refer to cells positively stained by Annexin V-FITC after 24 h treatment with antibody constructs at 20 nM. Caspase Assay refers to caspase activation of cells after 24 h treatment with antibody constructs at 20 nM.

Anti-CD38-Attenuated IFN Fusion Protein with Alternative Constant Region

A10.0 comprises an anti-CD38-attenuated IFN fusion protein in which the constant region of the protein is HC-L0-IFN-alpha (A145D) IgG4 (SEQ ID NO: 9). Using gene synthesis, the constant region of this protein was replaced with HC-L0-IFN-alpha (A145D) IgG1 (SEQ ID NO: 10), paired with A10.0 light chain (SEQ ID NO: 161) and given the designation A10.59. The protein was expressed and was found to be potent in functional assays (Table 28). While the majority of the proteins tested in the foregoing examples were constructed on the human IgG4 constant region, these data demonstrate that other antibody constant regions, such as human IgG1, may also be used, with the resultant antibody-attenuated IFN fusion construct having potent biologic activity equivalent to constructs that utilize a human IgG4 constant region.

TABLE 28 Annexin V Caspase Anti- H929 Assay (Fold Assay(Fold CD38- Flow change change Cell attenuated binding relative to relative to Proliferation IFN fusion (EC₅₀in untreated untreated Assay protein μg/mL) cells) cells) IC₅₀ (pM)* Figures A10.0 1.50 3.05 1.89 2081 21, 24, 25 A10.59 0.89 2.48 2.38 328.6 21, 24, 25 Annexin V Assay refer to cells positively stained by Annexin V-FITC after 24 h treatment with antibody constructs at 20 nM. Caspase Assay refers to caspase activation of cells after 24 h treatment with antibody constructs at 20 nM. N/T is Not Tested, *Data obtained from Cell Proliferation Assay assessed with cell culture supernatant.

Table 29 lists the pairing of variable heavy chain, variable light chain and constant region for each antibody described herein.

TABLE 29 Variable Heavy Chain Variable Light SEQ Constant Heavy SEQ ID NO: Region SEQ ID NO: (amino ID NO: Antibody Name (amino acid) acid) (amino acid) A02.10 19 14 9 A02.11 20 14 9 A02.112 34 65 10 A02.12 34 65 9 A02.13 35 65 9 A02.16 34 92 9 A02.17 34 93 9 A02.18 34 73 9 A02.19 34 74 9 A02.2 13 65 9 A02.20 34 75 9 A02.21 34 76 9 A02.22 34 77 9 A02.23 34 78 9 A02.24 34 79 9 A02.25 34 80 9 A02.26 34 81 9 A02.27 34 82 9 A02.28 34 83 9 A02.29 34 84 9 A02.3 17 65 9 A02.30 34 85 9 A02.31 34 86 9 A02.32 34 87 9 A02.33 34 88 9 A02.34 34 89 9 A02.35 34 90 9 A02.36 34 91 9 A02.37 34 66 9 A02.38 34 113 9 A02.39 34 112 9 A02.4 18 65 9 A02.40 111 65 9 A02.41 110 65 9 A02.43 110 113 9 A02.44 111 112 9 A02.46 34 67 9 A02.47 34 68 9 A02.48 34 69 9 A02.49 34 70 9 A02.5 19 65 9 A02.50 34 71 9 A02.51 34 72 9 A02.52 34 94 9 A02.53 34 95 9 A02.54 34 96 9 A02.55 34 97 9 A02.56 34 98 9 A02.57 34 99 9 A02.58 34 100 9 A02.59 34 101 9 A02.6 20 65 9 A02.60 34 102 9 A02.61 34 103 9 A02.62 34 104 9 A02.63 34 105 9 A02.64 34 106 9 A02.65 34 107 9 A02.66 34 108 9 A02.67 34 109 9 A02.8 17 14 9 A02.9 18 14 9 A10.1 165 161 9 A10.10 174 161 9 A10.11 175 161 9 A10.12 176 161 9 A10.13 177 161 9 A10.14 178 161 9 A10.15 179 161 9 A10.16 180 161 9 A10.17 156 181 9 A10.18 156 182 9 A10.19 156 183 9 A10.2 166 161 9 A10.20 156 184 9 A10.21 156 185 9 A10.22 156 186 9 A10.23 156 187 9 A10.24 156 188 9 A10.25 156 189 9 A10.26 156 190 9 A10.27 156 191 9 A10.28 156 192 9 A10.29 156 193 9 A10.3 167 161 9 A10.30 156 194 9 A10.31 156 195 9 A10.32 156 196 9 A10.35 197 161 9 A10.36 156 198 9 A10.38 152 161 9 A10.39 152 181 9 A10.4 168 161 9 A10.40 152 182 9 A10.41 152 183 9 A10.42 152 184 9 A10.43 152 185 9 A10.44 152 186 9 A10.45 152 187 9 A10.46 152 188 9 A10.47 152 189 9 A10.48 152 190 9 A10.49 152 191 9 A10.5 169 161 9 A10.50 152 192 9 A10.51 152 193 9 A10.52 152 194 9 A10.53 152 195 9 A10.54 152 196 9 A10.57 152 198 9 A10.59 156 161 10 A10.6 170 161 9 A10.7 171 161 9 A10.8 172 161 9 A10.9 173 161 9 A10A2.0 (chimeric) 148 157 9 A10A2.1 149 158 9 A10A2.10 150 160 9 A10A2.11 150 161 9 A10A2.12 150 162 9 A10A2.13 150 163 9 A10A2.14 150 164 9 A10A2.15 151 158 9 A10A2.16 151 159 9 A10A2.17 151 160 9 A10A2.18 151 161 9 A10A2.19 151 162 9 A10A2.2 149 159 9 A10A2.20 151 163 9 A10A2.21 151 164 9 A10A2.22 152 158 9 A10A2.23 152 159 9 A10A2.24 152 160 9 A10A2.25 152 161 9 A10A2.26 152 162 9 A10A2.27 152 163 9 A10A2.28 152 164 9 A10A2.29 153 158 9 A10A2.3 149 160 9 A10A2.30 153 159 9 A10A2.31 153 160 9 A10A2.32 153 161 9 A10A2.33 153 162 9 A10A2.34 153 163 9 A10A2.35 153 164 9 A10A2.36 154 158 9 A10A2.37 154 159 9 A10A2.38 154 160 9 A10A2.39 154 161 9 A10A2.4 149 161 9 A10A2.40 154 162 9 A10A2.41 154 163 9 A10A2.42 154 164 9 A10A2.43 154 158 9 A10A2.44 155 159 9 A10A2.45 155 160 9 A10A2.46 155 161 9 A10A2.47 155 162 9 A10A2.48 155 163 9 A10A2.49 155 164 9 A10A2.5 149 162 9 A10A2.50 156 158 9 A10A2.51 156 159 9 A10A2.52 156 160 9 A10A2.53 156 161 9 A10A2.54 156 162 9 A10A2.55 156 163 9 A10A2.56 156 164 9 A10A2.6 149 163 9 A10A2.7 149 164 9 A10A2.8 150 158 9 A10A2.9 150 159 9 A5D1.0 (chimeric) 114 125 9 A5D1.1 115 126 9 A5D1.10 116 129 9 A5D1.11 116 130 9 A5D1.12 116 131 9 A5D1.13 117 126 9 A5D1.14 117 127 9 A5D1.15 117 128 9 A5D1.16 117 129 9 A5D1.17 117 130 9 A5D1.18 117 131 9 A5D1.19 118 126 9 A5D1.2 115 127 9 A5D1.20 118 127 9 A5D1.21 118 128 9 A5D1.22 118 129 9 A5D1.23 118 130 9 A5D1.24 118 131 9 A5D1.25 119 126 9 A5D1.26 119 127 9 A5D1.27 119 128 9 A5D1.28 119 129 9 A5D1.29 119 130 9 A5D1.3 115 128 9 A5D1.30 119 131 9 A5D1.31 120 126 9 A5D1.32 120 127 9 A5D1.33 120 128 9 A5D1.34 120 129 9 A5D1.35 120 130 9 A5D1.36 120 131 9 A5D1.37 121 126 9 A5D1.38 121 127 9 A5D1.39 121 128 9 A5D1.4 115 129 9 A5D1.40 121 129 9 A5D1.41 121 130 9 A5D1.42 121 131 9 A5D1.43 122 126 9 A5D1.44 122 127 9 A5D1.45 122 128 9 A5D1.46 122 129 9 A5D1.47 122 130 9 A5D1.48 122 131 9 A5D1.49 123 126 9 A5D1.5 115 130 9 A5D1.50 123 127 9 A5D1.51 123 128 9 A5D1.52 123 129 9 A5D1.53 123 130 9 A5D1.54 123 131 9 A5D1.55 124 126 9 A5D1.56 124 127 9 A5D1.57 124 128 9 A5D1.58 124 129 9 A5D1.59 124 130 9 A5D1.6 115 131 9 A5D1.60 124 131 9 A5D1.7 116 126 9 A5D1.8 116 127 9 A5D1.9 116 128 9 A5E8.0 (chimeric) 132 143 9 A5E8.1 133 144 9 A5E8.10 135 145 9 A5E8.11 135 146 9 A5E8.12 135 147 9 A5E8.13 136 144 9 A5E8.14 136 145 9 A5E8.15 136 146 9 A5E8.16 136 147 9 A5E8.17 137 144 9 A5E8.18 137 145 9 A5E8.19 137 146 9 A5E8.2 133 145 9 A5E8.20 137 147 9 A5E8.21 138 144 9 A5E8.22 138 145 9 A5E8.23 138 146 9 A5E8.24 138 147 9 A5E8.25 139 144 9 A5E8.26 139 145 9 A5E8.27 139 146 9 A5E8.28 139 147 9 A5E8.29 140 144 9 A5E8.3 133 146 9 A5E8.30 140 145 9 A5E8.31 140 146 9 A5E8.32 140 147 9 A5E8.33 141 144 9 A5E8.34 141 145 9 A5E8.35 141 146 9 A5E8.36 141 147 9 A5E8.37 142 144 9 A5E8.38 142 145 9 A5E8.39 142 146 9 A5E8.4 133 147 9 A5E8.40 142 147 9 A5E8.5 134 144 9 A5E8.6 134 145 9 A5E8.7 134 146 9 A5E8.8 134 147 9 A5E8.9 135 144 9 X02.10 19 14 3 X02.100 13 58 3 X02.101 13 59 3 X02.102 13 60 3 X02.103 13 61 3 X02.104 13 62 3 X02.105 13 63 3 X02.106 13 64 3 X02.107 13 65 3 X02.108 32 14 3 X02.11 20 14 3 X02.110 33 14 3 X02.114 13 660 3 X02.115 13 661 3 X02.116 13 662 3 X02.117 13 663 3 X02.118 34 700 3 X02.119 34 701 3 X02.120 728 700 3 X02.121 729 700 3 X02.122 730 700 3 X02.123 731 700 3 X02.124 728 701 3 X02.125 729 701 3 X02.126 730 701 3 X02.127 731 701 3 X02.68 21 14 3 X02.69 22 14 3 X02.70 23 14 3 X02.71 24 14 3 X02.72 25 14 3 X02.73 26 14 3 X02.74 27 14 3 X02.75 28 14 3 X02.76 29 14 3 X02.77 30 14 3 X02.78 31 14 3 X02.8 17 14 3 X02.80 13 38 3 X02.81 13 39 3 X02.82 13 40 3 X02.83 13 41 3 X02.84 13 42 3 X02.85 13 43 3 X02.86 13 44 3 X02.87 13 45 3 X02.88 13 46 3 X02.89 13 47 3 X02.9 18 14 3 X02.90 13 48 3 X02.91 13 49 3 X02.92 13 50 3 X02.93 13 51 3 X02.94 13 52 3 X02.95 13 53 3 X02.96 13 54 3 X02.97 13 55 3 X02.98 13 56 3 X02.99 13 57 3 X10.100 720 706 3 X10.101 721 706 3 X10.102 722 706 3 X10.103 723 706 3 X10.104 739 706 3 X10.105 740 706 3 X10.106 741 706 3 X10.107 742 706 3 X10.108 720 707 3 X10.109 721 707 3 X10.110 722 707 3 X10.111 723 707 3 X10.112 739 707 3 X10.113 740 707 3 X10.114 741 707 3 X10.115 742 707 3 X10.116 720 708 3 X10.117 721 708 3 X10.118 722 708 3 X10.119 723 708 3 X10.120 739 708 3 X10.121 740 708 3 X10.122 741 708 3 X10.123 742 708 3 X10.124 720 709 3 X10.125 721 709 3 X10.126 722 709 3 X10.127 723 709 3 X10.128 739 709 3 X10.129 740 709 3 X10.130 741 709 3 X10.131 742 709 3 X10.132 720 710 3 X10.133 721 710 3 X10.134 722 710 3 X10.135 723 710 3 X10.136 739 710 3 X10.137 740 710 3 X10.138 741 710 3 X10.139 742 710 3 X10.140 720 711 3 X10.141 721 711 3 X10.142 722 711 3 X10.143 723 711 3 X10.144 739 711 3 X10.145 740 711 3 X10.146 741 711 3 X10.147 742 711 3 X10.60 156 704 3 X10.61 156 705 3 X10.62 156 706 3 X10.63 156 707 3 X10.64 156 708 3 X10.65 156 709 3 X10.66 156 710 3 X10.67 156 711 3 X10.68 720 161 3 X10.69 721 161 3 X10.70 722 161 3 X10.71 723 161 3 X10.72 739 161 3 X10.73 740 161 3 X10.74 741 161 3 X10.75 742 161 3 X10.76 152 704 3 X10.77 152 705 3 X10.78 152 706 3 X10.79 152 707 3 X10.80 152 708 3 X10.81 152 709 3 X10.82 152 710 3 X10.83 152 711 3 X10.84 720 704 3 X10.85 721 704 3 X10.86 722 704 3 X10.87 723 704 3 X10.88 739 704 3 X10.89 740 704 3 X10.90 741 704 3 X10.91 742 704 3 X10.92 720 705 3 X10.93 721 705 3 X10.94 722 705 3 X10.95 723 705 3 X10.96 739 705 3 X10.97 740 705 3 X10.98 741 705 3 X10.99 742 705 3 X910/12-HC-L0-IFN- 110 112 9 alpha (A145D) IgG4 X913/15-HC-L0-IFN- 111 113 9 alpha (A145D) IgG4

TABLE 30 SEQ ID NO: Type Description 1 AA Human CD38 2 AA Cynomolgus CD38 3 AA Human IgG4 constant heavy chain 4 AA Human IgG1 constant heavy chain 5 AA Human kappa constant region 6 AA Human lambda constant region 7 AA IFN-alpha2b 8 AA Intron A 9 AA HC-L0-IFN-alpha (A145D) IgG4 10 AA HC-L0-IFN-alpha (A145D) IgG1 11 AA A02.1 heavy chain 12 AA A02.1 light chain 13 AA A02.1 variable heavy chain 14 AA A02.1 variable light chain 15 AA X02.1VH variable heavy chain 16 AA IGHV4-61*01 germline sequence 17 AA X02.8VH variable heavy chain 18 AA X02.9VH variable heavy chain 19 AA X02.10VH variable heavy chain 20 AA X02.11VH variable heavy chain 21 AA X02.68VH variable heavy chain 22 AA X02.69VH variable heavy chain 23 AA X02.70VH variable heavy chain 24 AA X02.71VH variable heavy chain 25 AA X02.72VH variable heavy chain 26 AA X02.73VH variable heavy chain 27 AA X02.74VH variable heavy chain 28 AA X02.75VH variable heavy chain 29 AA X02.76VH variable heavy chain 30 AA X02.77VH variable heavy chain 31 AA X02.78VH variable heavy chain 32 AA X02.108VH variable heavy chain 33 AA X02.110VH variable heavy chain 34 AA A02.12VH variable heavy chain 35 AA A02.13VH variable heavy chain 36 AA A02.1VL variable light chain 37 AA IGLV5-37*01 germline sequence 38 AA X02.80VL variable light chain 39 AA X02.81VL variable light chain 40 AA X02.82VL variable light chain 41 AA X02.83VL variable light chain 42 AA X02.84VL variable light chain 43 AA X02.85VL variable light chain 44 AA X02.86VL variable light chain 45 AA X02.87VL variable light chain 46 AA X02.88VL variable light chain 47 AA X02.89VL variable light chain 48 AA X02.90VL variable light chain 49 AA X02.91VL variable light chain 50 AA X02.92VL variable light chain 51 AA X02.93VL variable light chain 52 AA X02.94VL variable light chain 53 AA X02.95VL variable light chain 54 AA X02.96VL variable light chain 55 AA X02.97VL variable light chain 56 AA X02.98VL variable light chain 57 AA X02.99VL variable light chain 58 AA X02.100VL variable light chain 59 AA X02.101VL variable light chain 60 AA X02.102VL variable light chain 61 AA X02.103VL variable light chain 62 AA X02.104VL variable light chain 63 AA X02.105VL variable light chain 64 AA X02.106VL variable light chain 65 AA X02.107VL variable light chain 66 AA A02.37VL variable light chain 67 AA A02.46VL variable light chain 68 AA A02.47VL variable light chain 69 AA A02.48VL variable light chain 70 AA A02.49VL variable light chain 71 AA A02.50VL variable light chain 72 AA A02.51VL variable light chain 73 AA A02.18VL variable light chain 74 AA A02.19VL variable light chain 75 AA A02.20VL variable light chain 76 AA A02.21VL variable light chain 77 AA A02.22VL variable light chain 78 AA A02.23VL variable light chain 79 AA A02.24VL variable light chain 80 AA A02.25VL variable light chain 81 AA A02.26VL variable light chain 82 AA A02.27VL variable light chain 83 AA A02.28VL variable light chain 84 AA A02.29VL variable light chain 85 AA A02.30VL variable light chain 86 AA A02.31VL variable light chain 87 AA A02.32VL variable light chain 88 AA A02.33VL variable light chain 89 AA A02.34VL variable light chain 90 AA A02.35VL variable light chain 91 AA A02.36VL variable light chain 92 AA X02.16VL variable light chain 93 AA X02.17VL variable light chain 94 AA A02.52VL variable light chain 95 AA A02.53VL variable light chain 96 AA A02.54VL variable light chain 97 AA A02.55VL variable light chain 98 AA A02.56VL variable light chain 99 AA A02.57VL variable light chain 100 AA A02.58VL variable light chain 101 AA A02.59VL variable light chain 102 AA A02.60VL variable light chain 103 AA A02.61VL variable light chain 104 AA A02.62VL variable light chain 105 AA A02.63VL variable light chain 106 AA A02.64VL variable light chain 107 AA A02.65VL variable light chain 108 AA A02.66VL variable light chain 109 AA A02.67VL variable light chain 110 AA 910VH variable heavy chain 111 AA 915 VH variable heavy chain 112 AA 912VL variable light chain 113 AA 913VL variable light chain 114 AA Chimeric 5D1-E2-VH 115 AA 5d1_1-f*01VH 116 AA 5d1_1-f*01VH94R 117 AA 5d1_1-18*01VH 118 AA 5d1_1-18*01VH71A 119 AA 5d1_1-24*01VH 120 AA 5d1_1-24*01VH71A 121 AA 5d1_1-24*01VH29F 122 AA 5d1_1-24*01VH94R 123 AA 5d1_1-45*01VH 124 AA 5d1_1-45*01VH71A 125 AA Chimeric 5D1VK 126 AA 5d1_1-5*01VK 127 AA 5d1_1-9*01VK 128 AA 5d1_1-12*01VK 129 AA 5d1_1D-13*01VK 130 AA 5d1_1D-16*01VK 131 AA 5d1_3-15*01VK 132 AA Chimeric 5E8 133 AA 5E8-1-f*01VH 134 AA 5E8-1-f*01VH30I 135 AA 5E8-1-f*01VH94R 136 AA 5E8-1-18*01VH 137 AA 5E8-1-18*01VH71A 138 AA 5E8-1-24*01VH 139 AA 5E8-1-24*01VH71A 140 AA 5E8-1-24*01VH94R 141 AA 5E8-1-45*01VH 142 AA 5E8-1-45*01VH71A 143 AA chimeric 5E8VK 144 AA 5E8-2-24*01VK 145 AA 5E8-2D-28*01VK 146 AA 5E8-2D-29*01VK 147 AA 5E8-2-30*01VK 148 AA 10A2 chimeric VH 149 AA 10A2_1-24*01VH 150 AA 10A2_1-24*01VH71A 151 AA 10A2_1-24*01VH94R 152 AA 10A2_1-24*0171A94R 153 AA 10A2_1-45*01VH 154 AA 10A2_1-45*01VH71A 155 AA 10A2_1-f*01VH 156 AA 10A2_1-f*01VH94R 157 AA 10A2 chimeric VK 158 AA 10A2_1-9*01Vk 159 AA 10A2_1-12*01Vk 160 AA 10A2_1D-13*01Vk 161 AA 10A2_1-33*01Vk 162 AA 10A2_3-11*02Vk 163 AA 10A2_3-15*01Vk 164 AA 10A2_6-21*01Vk 165 AA 10A2VH + A40E 166 AA 10A2VH + A40G 167 AA 10A2VH + A40H 168 AA 10A2VH + A40Q 169 AA 10A2VH + A40S 170 AA 10A2VH + A40V 171 AA 10A2VH + N35E 172 AA 10A2VH + N35P 173 AA 10A2VH + N35Q 174 AA 10A2VH + N35S 175 AA 10A2VH + R94E 176 AA 10A2VH + R94G 177 AA 10A2VH + R94P 178 AA 10A2VH + R94T 179 AA 10A2VH + K96G 180 AA 10A2VH + K96T 181 AA 10A2VK + K24E 182 AA 10A2VK + K24G 183 AA 10A2VK + K24P 184 AA 10A2VK + K24Q 185 AA 10A2VK + R54D 186 AA 10A2VK + I48D 187 AA 10A2VK + Y49E 188 AA 10A2VK + M89A 189 AA 10A2VK + M89E 190 AA 10A2VK + M89H 191 AA 10A2VK + M89K 192 AA 10A2VK + M89P 193 AA 10A2VK + M89Q 194 AA 10A2VK + M89S 195 AA 10A2VK + M89V 196 AA 10A2VK + Q90D 197 AA 10A2VH (AQ) + N98Q 198 AA 10A2VK (AV) + N53Q 199 AA X02.1VH FWR1 200 AA X02.1VH CDR1 201 AA X02.1VH FWR2 202 AA X02.1VH CDR2 203 AA X02.1VH FWR3 204 AA X02.1VH CDR3 205 AA X02.1VH FWR4 206 AA IGHV4-61*01 FWR1 207 AA IGHV4-61*01 CDR1 208 AA IGHV4-61*01 FWR2 209 AA IGHV4-61*01 FWR3 210 AA X02.8VH FWR3 211 AA X02.9VH FWR2 212 AA X02.10VH FWR3 213 AA X02.11VH FWR3 214 AA X02.68VH FWR1 215 AA X02.69VH FWR1 216 AA X02.70VH FWR3 217 AA X02.71VH FWR1 218 AA X02.72VH FWR3 219 AA X02.73VH FWR1 220 AA X02.74VH CDR3 221 AA X02.75VH FWR3 222 AA X02.76VH CDR3 223 AA X02.77VH CDR3 224 AA X02.78VH CDR1 225 AA X02.108 FWR3 226 AA X02.110VH FWR3 227 AA A02.12VH FWR3 228 AA A02.12VH CDR3 229 AA A02.13VH FWR2 230 AA A02.13VH FWR3 231 AA A02.13VH CDR3 232 AA A02.1VL FWR1 233 AA A02.1VL CDR1 234 AA A02.1VL FWR2 235 AA A02.1VL CDR2 236 AA A02.1VL FWR3 237 AA A02.1VL CDR3 238 AA A02.1VL FWR4 239 AA IGLV5-37*01 FWR1 240 AA IGLV5-37*01 CDR1 241 AA IGLV5-37*01 CDR2 242 AA IGLV5-37*01 FWR3 243 AA IGLV5-37*01 CDR3 244 AA X02.80VL CDR3 245 AA X02.81VL FWR3 246 AA X02.82VL FWR2 247 AA X02.83VL FWR1 248 AA X02.84VL FWR2 249 AA X02.84VL CDR2 250 AA X02.86VL CDR1 251 AA X02.87VL CDR3 252 AA X02.88VL CDR1 253 AA X02.89VL CDR2 254 AA X02.90VL CDR3 255 AA X02.91VL CDR1 256 AA X02.92VL CDR3 257 AA X02.93VL CDR3 258 AA X02.94VL CDR3 259 AA X02.95VL FWR1 260 AA X02.96VL FWR1 261 AA X02.97VL FWR1 262 AA X02.98VL CDR1 263 AA X02.99VL CDR1 264 AA X02.100VL CDR2 265 AA X02.101VL FWR3 266 AA X02.102VL FWR3 267 AA X02.103VL FWR3 268 AA X02.104VL CDR3 269 AA X02.105VL CDR3 270 AA X02.106VL CDR3 271 AA X02.107VL FWR3 272 AA A02.37VL FWR3 273 AA A02.37VL CDR3 274 AA A02.46VL FWR3 275 AA A02.46VL CDR3 276 AA A02.47VL FWR3 277 AA A02.48VL FWR3 278 AA A02.49VL FWR3 279 AA A02.50VL FWR3 280 AA A02.51VL FWR3 281 AA A02.18VL FWR2 282 AA A02.18VL FWR3 283 AA A02.19VL FWR2 284 AA A02.19VL FWR3 285 AA A02.20VL FWR2 286 AA A02.20VL FWR3 287 AA A02.21VL FWR2 288 AA A02.21VL FWR3 289 AA A02.22VL FWR2 290 AA A02.22VL FWR3 291 AA A02.23VL FWR2 292 AA A02.23VL FWR3 293 AA A02.24VL FWR2 294 AA A02.24VL FWR3 295 AA A02.25VL FWR2 296 AA A02.25VL FWR3 297 AA A02.26VL FWR2 298 AA A02.26VL FWR3 299 AA A02.27VL CDR2 300 AA A02.27VL FWR3 301 AA A02.28VL CDR2 302 AA A02.28VL FWR3 303 AA A02.29VL CDR2 304 AA A02.29VL FWR3 305 AA A02.30VL CDR2 306 AA A02.30VL FWR3 307 AA A02.31VL CDR2 308 AA A02.31VL FWR3 309 AA A02.32VL CDR2 310 AA A02.32VL FWR3 311 AA A02.33VL CDR2 312 AA A02.33VL FWR3 313 AA A02.34VL CDR2 314 AA A02.34VL FWR3 315 AA A02.35VL CDR2 316 AA A02.35VL FWR3 317 AA A02.36VL CDR2 318 AA A02.36VL FWR3 319 AA X02.16VL CDR1 320 AA X02.16VL FWR3 321 AA X02.16VL CDR3 322 AA X02.17VL CDR1 323 AA X02.17VL FWR3 324 AA X02.17VL CDR3 325 AA A02.52VL CDR1 326 AA A02.52VL CDR2 327 AA A02.52VL FWR3 328 AA A02.52VL CDR3 329 AA A02.53VL CDR1 330 AA A02.53VL CDR2 331 AA A02.53VL FWR3 332 AA A02.53VL CDR3 333 AA A02.54VL CDR1 334 AA A02.54VL CDR2 335 AA A02.54VL FWR3 336 AA A02.54VL CDR3 337 AA A02.55VL CDR1 338 AA A02.55VL CDR2 339 AA A02.55VL FWR3 340 AA A02.55VL CDR3 341 AA A02.56VL CDR1 342 AA A02.56VL CDR2 343 AA A02.56VL FWR3 344 AA A02.56VL CDR3 345 AA A02.57VL CDR1 346 AA A02.57VL CDR2 347 AA A02.57VL FWR3 348 AA A02.57VL CDR3 349 AA A02.58VL CDR1 350 AA A02.58VL CDR2 351 AA A02.58VL FWR3 352 AA A02.58VL CDR3 353 AA A02.59VL CDR1 354 AA A02.59VL CDR2 355 AA A02.59VL FWR3 356 AA A02.59VL CDR3 357 AA A02.60VL CDR1 358 AA A02.60VL CDR2 359 AA A02.60VL FWR3 360 AA A02.60VL CDR3 361 AA A02.61VL CDR1 362 AA A02.61VL CDR2 363 AA A02.61VL FWR3 364 AA A02.61VL CDR3 365 AA A02.62VL CDR1 366 AA A02.62VL CDR2 367 AA A02.62VL FWR3 368 AA A02.62VL CDR3 369 AA A02.63VL CDR1 370 AA A02.63VL CDR2 371 AA A02.63VL FWR3 372 AA A02.63VL CDR3 373 AA A02.64VL CDR1 374 AA A02.64VL CDR2 375 AA A02.64VL FWR3 376 AA A02.64VL CDR3 377 AA A02.65VL CDR1 378 AA A02.65VL CDR2 379 AA A02.65VL FWR3 380 AA A02.65VL CDR3 381 AA A02.66VL CDR1 382 AA A02.66VL CDR2 383 AA A02.66VL FWR3 384 AA A02.66VL CDR3 385 AA A02.67VL CDR1 386 AA A02.67VL CDR2 387 AA A02.67VL FWR3 388 AA A02.67VL CDR3 389 AA 5D1.1VH FWR1 390 AA 5D1.1VH CDR1 391 AA 5D1.1VH FWR2 392 AA 5D1.1VH CDR2 393 AA 5D1.1VH FWR3 394 AA 5D1.1VH CDR3 395 AA 5D1.1VH FWR4 396 AA 5D1.2VH FWR1 397 AA 5D1.2VH FWR2 398 AA 5D1.2VH CDR2 399 AA 5D1.2VH FWR3 400 AA 5D1.3VH FWR1 401 AA 5D1.3VH FWR2 402 AA 5D1.3VH CDR2 403 AA 5D1.3VH FWR3 404 AA 5D1.4VH FWR1 405 AA 5D1.4VH FWR2 406 AA 5D1.4VH CDR2 407 AA 5D1.4VH FWR3 408 AA 5D1.5VH FWR1 409 AA 5D1.5VH FWR2 410 AA 5D1.5VH CDR2 411 AA 5D1.5VH FWR3 412 AA 5D1.6VH FWR1 413 AA 5D1.6VH FWR2 414 AA 5D1.6VH CDR2 415 AA 5D1.6VH FWR3 416 AA 5D1.7VH FWR1 417 AA 5D1.7VH FWR2 418 AA 5D1.7VH CDR2 419 AA 5D1.7VH FWR3 420 AA 5D1.8VH FWR1 421 AA 5D1.8VH FWR2 422 AA 5D1.8VH CDR2 423 AA 5D1.8VH FWR3 424 AA 5D1.9VH FWR1 425 AA 5D1.9VH FWR2 426 AA 5D1.9VH CDR2 427 AA 5D1.9VH FWR3 428 AA 5D1.10VH FWR1 429 AA 5D1.10VH FWR2 430 AA 5D1.10VH CDR2 431 AA 5D1.10VH FWR3 432 AA 5D1.11VH FWR1 433 AA 5D1.11VH FWR2 434 AA 5D1.11VH CDR2 435 AA 5D1.11VH FWR3 436 AA 5D1.1VL FWR1 437 AA 5D1.1VL CDR1 438 AA 5D1.1VL FWR2 439 AA 5D1.1VL CDR2 440 AA 5D1.1VL FWR3 441 AA 5D1.1VL CDR3 442 AA 5D1.1VL FWR4 443 AA 5D1.2VL FWR1 444 AA 5D1.2VL FWR2 445 AA 5D1.2VL FWR3 446 AA 5D1.2VL FWR4 447 AA 5D1.3VL FWR1 448 AA 5D1.3VL FWR2 449 AA 5D1.3VL FWR3 450 AA 5D1.3VL FWR4 451 AA 5D1.4VL FWR1 452 AA 5D1.4VL FWR2 453 AA 5D1.4VL FWR3 454 AA 5D1.4VL FWR4 455 AA 5D1.5VL FWR1 456 AA 5D1.5VL FWR2 457 AA 5D1.5VL FWR3 458 AA 5D1.5VL FWR4 459 AA 5D1.6VL FWR1 460 AA 5D1.6VL FWR2 461 AA 5D1.6VL FWR3 462 AA 5D1.6VL FWR4 463 AA 5D1.7VL FWR1 464 AA 5D1.7VL FWR2 465 AA 5D1.7VL FWR3 466 AA 5E8.1VH FWR1 467 AA 5E8.1VH CDR2 468 AA 5E8.1VH FWR3 469 AA 5E8.1VH CDR3 470 AA 5E8.2VH FWR1 471 AA 5E8.2VH CDR2 472 AA 5E8.3VH FWR1 473 AA 5E8.3VH CDR2 474 AA 5E8.4VH FWR1 475 AA 5E8.4VH CDR2 476 AA 5E8.5VH FWR1 477 AA 5E8.5VH CDR2 478 AA 5E8.6VH FWR1 479 AA 5E8.6VH CDR2 480 AA 5E8.7VH FWR1 481 AA 5E8.7VH CDR2 482 AA 5E8.8VH FWR1 483 AA 5E8.8VH CDR2 484 AA 5E8.9VH FWR1 485 AA 5E8.9VH CDR2 486 AA 5E8.10VH FWR1 487 AA 58E.10VH CDR2 488 AA 5E8.11VH FWR1 489 AA 58E.11VH CDR2 490 AA 5E8.1VL FWR1 491 AA 5E8.1VL CDR1 492 AA 5E8.1VL FWR2 493 AA 5E8.1VL CDR2 494 AA 5E8.1VL FWR3 495 AA 5E8.1VL CDR3 496 AA 5E8.1VL FWR4 497 AA 5E8.2VL FWR1 498 AA 5E8.2VL FWR2 499 AA 5E8.2VL FWR3 500 AA 5E8.2VL FWR4 501 AA 5E8.3VL FWR1 502 AA 5E8.3VL FWR2 503 AA 5E8.3VL FWR3 504 AA 5E8.3VL FWR4 505 AA 5E8.4VL FWR1 506 AA 5E8.4VL FWR2 507 AA 5E8.4VL FWR3 508 AA 5E8.4VL FWR4 509 AA 5E8.5VL FWR1 510 AA 5E8.5VL FWR2 511 AA 5E8.5VL FWR3 512 AA 5E8.5VL FWR4 513 AA 10A2.1VH FWR1 514 AA 10A2.1VH CDR1 515 AA 10A2.1VH FWR2 516 AA 10A2.1VH CDR2 517 AA 10A2.1VH FWR3 518 AA 10A2.1VH CDR3 519 AA 10A2.1VH FWR4 520 AA 10A2.2VH FWR2 521 AA 10A2.3VH FWR2 522 AA 10A2.4VH FWR2 523 AA 10A2.5VH FWR2 524 AA 10A2.6VH FWR2 525 AA 10A2.7VH FWR2 526 AA 10A2.8VH CDR1 527 AA 10A2.9VH CDR1 528 AA 10A2.10VH CDR1 529 AA 10A2.11VH CDR1 530 AA 10A2.12VH FWR3 531 AA 10A2.13VH FWR3 532 AA 10A2.14VH FWR3 533 AA 10A2.15VH FWR3 534 AA 10A2.16VH CDR3 535 AA 10A2.17VH CDR3 536 AA 10A2.18VH CDR3 537 AA 10A2.19VH FWR1 538 AA 10A2.19VH FWR2 539 AA 10A2.19VH CDR2 540 AA 10A2.19VH FWR3 541 AA 10A2.19VH FWR4 542 AA 10A2.20VH FWR1 543 AA 10A2.20VH FWR2 544 AA 10A2.20VH CDR2 545 AA 10A2.20VH FWR3 546 AA 10A2.20VH FWR4 547 AA 10A2.21VH FWR1 548 AA 10A2.21VH FWR2 549 AA 10A2.21VH CDR2 550 AA 10A2.21VH FWR3 551 AA 10A2.21VH FWR4 552 AA 10A2.22VH FWR1 553 AA 10A2.22VH FWR2 554 AA 10A2.22VH CDR2 555 AA 10A2.22VH FWR3 556 AA 10A2.22VH FWR4 557 AA 10A2.23VH FWR1 558 AA 10A2.23VH FWR2 559 AA 10A2.23VH CDR2 560 AA 10A2.23VH FWR3 561 AA 10A2.23VH FWR4 562 AA 10A2.24VH FWR1 563 AA 10A2.24VH FWR2 564 AA 10A2.24VH CDR2 565 AA 10A2.24VH FWR3 566 AA 10A2.24VH FWR4 567 AA 10A2.25VH FWR1 568 AA 10A2.25VH FWR2 569 AA 10A2.25VH CDR2 570 AA 10A2.25VH FWR3 571 AA 10A2.25VH FWR4 572 AA 10A2.26VH FWR1 573 AA 10A2.26VH FWR2 574 AA 10A2.26VH CDR2 575 AA 10A2.26VH FWR3 576 AA 10A2.26VH FWR4 577 AA 10A2.27VH FWR1 578 AA 10A2.27VH FWR2 579 AA 10A2.27VH CDR2 580 AA 10A2.27VH FWR3 581 AA 10A2.27VH FWR4 582 AA 10A2.1VL FWR1 583 AA 10A2.1VL CDR1 584 AA 10A2.1VL FWR2 585 AA 10A2.1VL CDR2 586 AA 10A2.1VL FWR3 587 AA 10A2.1VL CDR3 588 AA 10A2.1VL FWR4 589 AA 10A2.2VL CDR1 590 AA 10A2.3VL CDR1 591 AA 10A2.4VL CDR2 592 AA 10A2.5VL FWR2 593 AA 10A2.6VL FWR2 594 AA 10A2.7VL CDR3 595 AA 10A2.8VL CDR3 596 AA 10A2.9VL CDR3 597 AA 10A2.10VL CDR3 598 AA 10A2.11VL CDR3 599 AA 10A2.12VL CDR3 600 AA 10A2.13VL CDR3 601 AA 10A2.14VL CDR3 602 AA 10A2.15VL CDR3 603 AA 10A2 16VL CDR3 604 AA 10A2.17VL CDR3 605 AA 10A2.18VL CDR2 606 AA 10A2.19VL CDR3 607 AA 10A2.20VL FWR1 608 AA 10A2.20VL CDR1 609 AA 10A2,20VL FWR2 610 AA 10A2.20VL CDR2 611 AA 10A2.20VL FWR3 612 AA 10A2.20VL CDR3 613 AA 10A2.20VL FWR4 614 AA 10A2.21VL FWR1 615 AA 10A2.21VL FWR2 616 AA 10A2.21VL FWR3 617 AA 10A2.21VL FWR4 618 AA 10A2.22VL FWR1 619 AA 10A2.22VL FWR2 620 AA 10A2.22VL FWR3 621 AA 10A2.22VL FWR4 622 AA 10A2.23VL FWR1 623 AA 10A2.23VL FWR2 624 AA 10A2.23VL FWR3 625 AA 10A2.23VL FWR4 626 AA 10A2.24VL FWR1 627 AA 10A2.24VL FWR2 628 AA 10A2.24VL FWR3 629 AA 10A2.24VL FWR4 630 AA 10A2.25VL FWR1 631 AA 10A2.25VL FWR2 632 AA 10A2.25VL FWR3 633 AA 10A2.25VL FWR4 634 AA 10A2.26VL FWR1 635 AA 10A2.26VL FWR2 636 AA 10A2.26VL FWR3 637 AA 10A2.26VL FWR4 638 AA 10A2.27VL FWR1 639 AA 10A2.27 VL FWR2 640 AA 10A2.27VL FWR3 641 AA 10A2.27VL FWR4 642 AA Gly4Ser1 643 AA Gly4Ser1 x 2 644 AA Gly4Ser1 x 3 645 AA Gly4Ser1 x 4 646 AA Gly4Ser1 x 5 647 AA IFN-alpha2b A145D 648 AA Trunc IFN-alpha2b 649 AA Trunc IFN-alpha2b A145D 650 AA IFN-alpha2b A145G 651 AA Trunc IFN-alpha2b A145G 652 AA IgG4 IFN-alpha2b A145D 653 AA IgG4 IFN-alpha2b A145G 654 AA IgG4 S228P IFN-alpha2b A145G 655 AA IgG1 IFN-alpha2b A145G 656 AA IgG1 YTE IFN-alpha2b A145D 657 AA IgG1 YTE IFN-alpha2b A145G 658 AA IgG4 YTE IFN-alpha2b A145D 659 AA A02 consensus variable heavy 660 AA X02.114VL 661 AA X02.115VL 662 AA X02.116VL 663 AA X02.117VL 664 AA A02 consensus variable light 665 AA A10 consensus variable heavy 666 AA A10 consensus variable light 667 DNA A02.12VH 668 DNA X02.9VH 669 DNA X02.107VL 670 DNA A02.47VL 671 DNA A02.31VL 672 DNA A02.33VL 673 DNA X02.16VL 674 DNA X02.17VL 675 DNA X02.114VL 676 DNA X02.115VL 677 DNA X02.116VL 678 DNA X02.117VL 679 DNA 10A2VH + A40E 680 DNA 10A2VH + A40G 681 DNA 10A2VH + A40H 682 DNA 10A2VH + A40Q 683 DNA 10A2VH + K96G 684 DNA 10A2VH + K96T 685 DNA 10A2_1-f*01VH94R 686 DNA 10A2VH (AQ) + N98Q 687 DNA 10A2-1-24*0171A94R 688 DNA 10A2_1-33*01Vk 689 DNA 10A2VK + K24G 690 DNA 10A2VK + K24Q 691 DNA 10A2VK + R54D 692 DNA 10A2VK + M89A 693 DNA 10A2VK (AV) + N53Q 694 AA IgG4 YTE IFN-alpha2b A145G 695 DNA 910VH variable heavy chain 696 AA 10A2VK + K24G CDR1 697 AA 910VH CDR1 698 AA 910VH CDR2 699 AA 910VH CDR3 700 AA X02.118 variable light chain 701 AA X02.119 variable light chain 702 DNA X02.118 variable light chain 703 DNA X02.119 variable light chain 704 AA X10.60 variable light chain 705 AA X10.61 variable light chain 706 AA X10.62 variable light chain 707 AA X10.63 variable light chain 708 AA X10.64 variable light chain 709 AA X10.65 variable light chain 710 AA X10.66 variable light chain 711 AA X10.67 variable light chain 712 DNA X10.60 variable light chain 713 DNA X10.61 variable light chain 714 DNA X10.62 variable light chain 715 DNA X10.63 variable light chain 716 DNA X10.64 variable light chain 717 DNA X10.65 variable light chain 718 DNA X10.66 variable light chain 719 DNA X10.67 variable light chain 720 AA X10.68 variable heavy chain 721 AA X10.69 variable heavy chain 722 AA X10.70 variable heavy chain 723 AA X10.71 variable heavy chain 724 DNA X10.68 variable heavy chain 725 DNA X10.69 variable heavy chain 726 DNA X10.70 variable heavy chain 727 DNA X10.71 variable heavy chain 728 AA X02.120 variable heavy chain 729 AA X02.121 variable heavy chain 730 AA X02.122 variable heavy chain 731 AA X02.123 variabel heavy chain 732 DNA X02.120 variable heavy chain 733 DNA X02.121 variable heavy chain 734 DNA X02.122 variable heavy chain 735 DNA X02.123 variable heavy chain 736 AA 910 variable heavy consensus 737 AA X02.122VH CDR2 738 AA X02.123VH CDR2 739 AA X10.72 variable heavy chain 740 AA X10.73 variable heavy chain 741 AA X10.74 variable heavy chain 742 AA X10.75 variable heavy chain 743 DNA X10.72 variable heavy chain 744 DNA X10.73 variable heavy chain 745 DNA X10.74 variable heavy chain 746 DNA X10.75 variable heavy chain 747 AA X10.64VL CDR2 748 AA 910 VH FRW1 749 AA 910 VH FRW2 750 AA X10.120VH FRW2 751 AA 910 VH FRW3 752 AA X10.121VH FRW3 753 AA 910VH FRW4

The disclosure is not limited to the embodiments described and exemplified above, but is capable of variation and modification within the scope of the appended claims. 

We claim:
 1. A method for treating B-cell lymphoma, multiple myeloma, non-Hodgkin's lymphoma, chronic myelogenous leukemia, chronic lymphocytic leukemia, or acute myelogenous leukemia in a subject, the method comprising: administering to the subject a recombinant antibody that specifically binds to CD38, the recombinant antibody comprising the heavy chain complementarity determining region 1 (CDR1), CDR2, and CDR3 of SEQ ID NO: 665 and the light chain CDR1, CDR2, and CDR3 of SEQ ID NO: 666 in an amount effective to thereby treat the B-cell lymphoma, multiple myeloma, non-Hodgkin's lymphoma, chronic myelogenous leukemia, chronic lymphocytic leukemia, or acute myelogenous leukemia.
 2. The method of claim 1, wherein the recombinant antibody is a humanized antibody.
 3. The method of claim 1, wherein the antibody is fused to an attenuated human interferon alpha-2b.
 4. The method of claim 3, wherein the attenuated human interferon alpha-2b comprises an alanine to aspartic acid substitution at position 145 relative to the amino acid sequence of SEQ ID NO:
 648. 5. The method of claim 3, wherein the attenuated human interferon alpha 2b comprises the amino acid sequence of SEQ ID NO: 647, SEQ ID NO: 649, SEQ ID NO: 650, or SEQ ID NO:
 651. 6. The method of claim 5, wherein the attenuated human interferon alpha 2b comprises the amino acid sequence of SEQ ID NO:
 649. 7. The method of claim 1, wherein the recombinant antibody comprises a human IgG1 heavy chain constant region.
 8. The method of claim 1, wherein the recombinant antibody comprises a human IgG4 heavy chain constant region.
 9. The method of claim 8, wherein the human IgG4 heavy chain constant region comprises a proline at position 228 according to the EU numbering system.
 10. The method of claim 1, wherein the heavy chain CDR1 comprises the amino acid sequence of SEQ ID NO: 514, the heavy chain CDR2 comprises the amino acid sequence of SEQ ID NO: 516, the heavy chain CDR3 comprises the amino acid sequence of SEQ ID NO: 518, the light chain CDR1 comprises the amino acid sequence of SEQ ID NO: 608, the light chain CDR2 comprises the amino acid sequence of SEQ ID NO: 591, and the light chain CDR3 comprises the amino acid sequence of SEQ ID NO:
 612. 11. The method of claim 10, wherein the recombinant antibody is fused to an attenuated human interferon alpha-2b comprising the amino acid sequence of SEQ ID NO:
 649. 12. The method of claim 1, wherein the recombinant antibody comprises a heavy chain variable region comprising the amino acid sequence of SEQ ID NO: 156 and a light chain variable region comprising the amino acid sequence of SEQ ID NO:
 185. 13. The method of claim 12, wherein the recombinant antibody is fused to an attenuated human interferon alpha-2b comprising the amino acid sequence of SEQ ID NO:
 649. 